Can you easily and quickly solo High CZ each time in a Viper IV like you can in pretty much any medium ship? Can you kill Hydra? Can you beat any Medium-Large ship in PVP? Doubt so. Viper III is fastest ship in the game. Even under the weight, it will leave MkIV in dust and outmaneuver it at every turn. This is the only advantage of any small ship can have in combat. Vulture is much tougher, and x2 C3 hardpoints is a serious argument, but still it is far from even PVE meta or being efficient much, it's just a better option for small player budget. Haz RES is not really an argument either, since people go there on stock Sideys to make early bank, and learn combat - training wheels.
PvP I don't know as I don't do it. ED isn't built for it IMO.
All the other stuff, yup Viper IV can easily do it.
Talking about small/new player budget yet you pick a ship that cost 2-3x the Viper IV, doesn't handle as well and in PvE the small fast 'advantage' pretty much isn't there as nothing the NPC's can throw at you will come close to beating a V4.
If you want to talk about V3 vs V4 there is only 2 outcomes from that match up. V3 runs away or gets smashed. Simple. Once you start loading up the viper 3 the 'speed advantage' quickly disappears, ask any racer or hooner as they know this very intimately.
The Vulture yes has the higher damage potential vs the V4 but it's bigger (easier) to hit has a crap boost profile compared to V4, meaning it gets outflown easier and the effects of 2x the weapons will easily make up for any damage advantage.
If you want a small ship that CAN seriously kick ass and fly like a deamon then the Viper V is a superb ship for it. Vulture is also a good ship but IMO the V4 still wins.