All bits you mention are simply answered by a look at the chart legend...
Yes, but I don't have to do that when I fly to France, Italy, Switzerland, ... These charts are called "ICAO" charts for a reason and ICAO put some effort into standardisation back then (in 1949!).
That is why the Jeppesen VFR charts were great...
... they had to, because I was one of their "beta testers" in the early nineties :-) They even implemented some modifications that I proposed - but I certainly was not the only one to propose them as the first versions had some very obvious deficiencies. Let's hope their electronic version is as good.
The Belfast example is a real nightmare to read, I wouldn't dare to fly there VFR with this kind of chart.
...would you instantly realize that you can happily fly overhead Belfast City at, say, 2,500ft?
No, certainly not. Looking closely, I see that the Belfast City control zone (class D) reaches from the surface to 2000ft. Above that is class E going form 2000ft to FL105. But it is surrounded from all sides by more "D" aispaces with very different vertical extensions so that it would be really challenging to get into that bit of class "E" and out of it again.
And what are the holding patterns for (there's one in the top right corner labelled "MAGEE")?
And what are the holding patterns for (there's one in the top right corner labelled "MAGEE")?
It really is a nightmare to get used to VFR in this area, I for one find it extremely difficult to figure out which lines apply to which pieces of airspace with which vertical extent.
Regarding the MAGEE hold. I do not know if this is correct or not but I assume it is due to it being part of the IAP for Belfast city and also being outside uncontrolled airspace, it is marked for a similarly reason that we have the the IAP final approach track marked outside controlled airspace.
That standard is quite new, Germany transitioned to it only recently. And BTW, it does not standardise how gliding sites are depicted. And every country has their own things: Germany depicts runway direction and surface (which I quite like) but this is against the standard. France does not shade the CTRs fully, most surrounding countries do. France has special symbology for . The base maps all look different. and so on and so on.
There are no two ways around it - when flying internationally, you will have to learn how to read their maps, learn about their special rules from their AIP, and so on. You can reduce this by buying standardised charts and notes from Jeppesen, formerly Bottlang.
And, unfortunately, SERA does not change a thing because every country can still file differences where it matters. Germany will still have "Minimum 2000ft cross country", UK will still have their special version of the glide clear rule, France will still have their minimum overflight heights for cities. Plus ça change...
And since everything the central aviation agencies in Europe (EASA and Eurocontrol) produce ends in a big mess, long may it continue - the alternative is likely to be much worse.
Hmmm....
That Belfast chart is atrocious. I had never seen that before. One can work it out if one actually reads what it says (it isn't logically ambiguous, in the way I think some Jepp VFR charts are) but I don't think anything as bad exists elsewhere in the UK.
Otherwise, the problems people are having here are caused simply by not reading the legends on the chart. That is always going to be a problem until we get standardised VFR charts for all of Europe, which is very obviously never going to happen.
The Swingate/1.0 thingy means an area you want to keep out of, SFC-1000ft AGL. Whether one can fly through danger areas is another topic. There are rules for each one but the safe thing is to avoid them.
The holding pattern is a daft idea. The CAA drops a few of those in where they have room, to let it be known there is a hold which is OCAS and VFR traffic ought to keep an extra lookout. Of course VFR traffic just ignores it because a PPL holder is not supposed to know what a hold is. Same for the chevrons that depict instrument approaches; a nice idea (though again only some are depicted) but mostly ignored. The only way to fix that is to put all IAPs in CAS, which thankfully won't happen in the UK.
Everything not shown as an airspace class is Class G and you can go where you like, VFR or IFR, non-radio. There are some TMZs.
Instrument approaches inside and outside controlled airspace:
No proper handovers:
Fly from Old Buckenham to Stapleford in an anti-clockwise direction around London. Talk to Stansted, Farnborough N, Heathrow, Farnborough SW, Gatwick, Farnborough SE, London City, and Stapleford. Find yourself not being handed over. So you end up telling every unit almost the same thing: Who you are (G-ABCD) Your aircraft type (Cessna 152) Where you're from (Old Buckenham) Where you're going (Stapleford) Where you are (15 miles to the north) Your altitude (2400 feet) What you require (transit or traffic service) and change squawk codes every 5-10 minutes for every unit you deal with.
Do it wrong and you'll be busted for infringing airspace.
Even though it is not ICAO-compliant the approach used in Germany for instrument approaches outside controlled airspace is rather good in my opinion. Airspace F is established around each aerodrome, covering the space from the ground up to the start of E (usually 2000ft AGL). Every VFR map has it depicted and VFR pilots that don't understand it (I guess more than 80%) just stay away. For VFR pilots that do understand it, it means they know it's smart to tune the AFIS frequency and which direction to expect traffic from.
PS: Airspace F is the same as G but with different VMC criteria and IFR is allowed in F whereas it's prohibited in G.
I guess more than 80%...
99 comes closer ;-) But this is, because 90 percent of the PPL instructors have no idea about airspaces. At one of my frequent destinations, they even hung up a large poster saying something like "Airspace F is not prohibited airspace!" because as soon as F was installed, the number of VFR visits declined.
... and IFR is allowed in F ...
Yes, but as it is uncontrolled airspace, only one IFR movement at one time. Again, this is something that maybe only 80% of all IFR pilots know, thereby generating lots of unnecessary delays for other traffic. So if ever you fly IFR to a German airfield with airspace F, cancel IFR as soon as you are safely in VMC conditions to give other departing and arriving IFR traffic a chance to proceed. Especially when flying into and out of EDTY please...
And one other thing: Flying IFR in aispace F gives you no special rights (again, 80% of pilots do not seem know this) over other traffic. If you come in on the ILS and there is VFR traffic in the pattern, that traffic has the usual right of way. Even if the radio operator says something like "D-EABC please extend your downwind leg, I have a Ryanair Boing on the ILS" D-EABC does not have to comply with that instruction and may legally force the Boeing to go around.
busting airspace
Only if you are using ATC to do navigation for you 
In practice, the German Class F approaches work exactly the same way as the approaches in UK Class G - ATC provides procedural separation by only allowing one aircraft on the final approach at a time.
The only differences are
ah, yes, and different VMC minima in Class F. Which of course are adhered to in all cases.
