With 6 dispel dice you may not need those dispel scrolls unless you go up against a lot of magic heavy armies.
Personally, i’d drop the sneaky gits and just field regular hobgoblins with Light armour and shield. They’re better value for points, I think.
I would drop the black orcs and bulk up your warrior units to at least 25. If your characters are going in them (which I assume they are) then those units will probably take some missile fire hits. Consider buying a Warbanner as a unit magic standard for the unit that your BSB is going in.
The list does tend to lack mobility (i.e. Bull Centaurs, Wolf Riders and/or flying monsters) but given your goal of using BfSP stuff to keep costs down that’s understandable. Have you considered using the BfSP Spiders Riders as “counts as” Wolf Riders?
Just using the spiders as wolves is something I didn’t think of (thought of maybe finding some wolves for them if possible…) but, is just using them as wolves acceptable in normal tournaments, for example (yeah I guess it could vary…but…generally?)
That list looks a lot better to me. The fast cav should give you a lot more flexibilty during the game.
As for the “counts as” in tournaments… well, “counts as” is an accepted convention in Warhammer, so you should be able to do it, although I guess if the tournament scoring factors WYSIWYG (what you see is what you get) into the scoring you may lose some points for using “counts as” models. I would just ask the tournament organiser beforehand. So long as you make a point of letting your opponent know before the game starts that you are using them as Wolf Riders I doubt if anyone would care. I use my Spider Riders as Wolf Riders and nobody I play against seems to mind.