@TheDaddy
1) You can check the about window from your Workbench menu, Update 3 contain Kickstart 53.22/workbench 53.7
2) No at the moment but there is AmiUpdate to update "automatically" your software
3) Yes exactly
4) Quake 1 is surely more performer because is less complex
5) Descent Freespace is also OS4 native so it should work fine, WipeOut 2097 is a bit complex to say, on AmigaOne it works perfectly (even with some little graphic issue that are currently in the fixing stage) but on other machine it doesn't work so fine (freeze) expecially on Sam Flex ...
So all depend on your machine and your luck
6) A lot .. check OS4depot
7) At the moment (native) i will say Cinnamon Writer
8) YAM is surely the best but if you disperately need IMAP4 you should point your mouse to SimpleMail
9) Sadly not :-/
10) To be honest not so decently on a plain Sam440 or a Sam Flex but surely you can enjoy them with a Sam460, an AmigaOne/Pegasos 2 and of course on an X1000
11) You must use ClipDown for now ...
12) We have many solution here and all solutions are perfectly fine, we have TuneNet, AmigaAMP, PlayOGG, PlayCDDA and many many others, it's up to you to choose the best or what you like more ...
13) The best solution right now is RunInUAE from our ChrisH
14) Don't know really
15) No idea, maybe be more specific