All these you mentioned are indeed lacking from GTA V, but they were wearing off real quick. The only things I bothered with were the stadium events, and the RC races which were difficult, the rest were bland, boring and repetitive. I suggest you check out this post from IGN called 100 little things that will blow your mind in GTA V or something like that. VC doesn't have most of these, if any at allVigilante, paramedic, firefighter, import/export, illegal ice cream selling (child labour?), hotring cars and race, bloodring derby, dirtring, rc cars, all I can think of at the moment. GTA V was supposed to bring back and improve the classic activities we loved that IV lacked, instead of replacing them with sh*t.
To me, I had much better experience with Vice City than I did with GTA V. VC had much better story, much better protagonist and antagonists, much better characters, much better vibe and feel, much better features and content relative to its size.
You're right, HD VC in RAGE/Euphoria would have made V look like sh*t.
Apart from that,
Can you costumize cars in VC? No
Can you play a bloat of mini-games? Not really
Can you costumize your character apart from preset oufits? No
Do you have random encounters? No
Scuba Dive? Nope
Get drunk while hanging out with your friends? Still, no.
All that, plus more and the overall felling of realism and immersion