at least web ball assist is a slow moving projectile allowing some characters to get in behind it. and you can get around using OTG assists with spiderman, he is one of the few characters with a ground bounce AND wall bounce and i've yet to see combos with him that combine the two.I actually know plenty of UWT setups. The problem is a large majority of the cast can actually escape fairly easily. For the most part I already know all the chars I can kill in a combo without the use of UTW and in tourney situations its just personal preference but I would rather not take the chance just to save 1 meter.
He did get a lot of buffs. He's def not as abysmal as he was in MvC2. The problem is though unless you build a team completely around him he is a fairly sub-par. Poor assists, MS doesn't DHC well, overly reliant on OTG assists, etc.
for instance you can Dragon punch Light spider sting and continue a ground combo into qcf L web ball which combos into his crawler assault, which is a strong wall bounce, allowing him to continue the ground combo until he decides to launch in which case you can do an air string into maximum spider, which SHOULD provide quite a bit of damage and power, the same as an OTG + wall bounce (wesker) character or ground bounce + OTG (pheonix) character.