And the bolded is why I don't think him alone would be great "alone"... "in this universe". There was always some tie to the Avengers/Chitauri or Tony Stark and Iron-Man with this crop of villains to add to the scale of the threat.
By no means am I saying he can't be a great villain, I'm saying I don't think he would be the draw to casual fans/movie goers. I mean it's spider-man so it's going to make doe...but in this MCU, they either villains to other movies, or they team them up to add to scale.
- Vulture/Chitauri/Avengers 1 (story arc)
- Mysterio/Tony Stark/Ironman (story arc)
- Whiplash/Justin Hammer (team up)
- Mandarin/Killian (team up)
- Hela/Surtur (team up)
- winter soldier/Pierce/crossbones (team up)
- Ultron/Quicksilver/Scarlet Witch (team up)
- Killmonger/Klaue (team up and story arc)
You can literally do this for every MCU movie. I just don't see Kraven being alone.
If Kraven was the Killmonger to Kingpin or JJJ's Klaue, then perhaps I could see it.