Specifically?
1.Maneuvers are not spells. Crunch-wise, they share zero spell-exclusive mechanics, while fluff-wise, maneuvers run the gamut from realistic(Heya, Counter-Charge!), to thematically appropriate(Such as Conan's Iron Heart Surge), to those that are indeed spell-ish in nature(Shadow Teleport line). The first two are appropriate to any fighter-type, and the last is mostly exclusive to the classes that actually are supposed to be getting semi-magical abilities.
2.Warblade is the only truly non-magical fighter from ToB, and he does a pretty good job of that. Most of his maneuvers and stances are oriented into doing the things real people can do, but better.
3.Crusader is a Paladin remake. Denying him spell-ish things is a clear denial of what the original already was.
4.Swordsage is an amalgam of monk/rogue/wizard. As a result, he should feel like you're playing something very mystical in nature. Some of their maneuvers are spells re-crunched, but you're common horizon walker can already teleport, so why not the swordsage?
5.Maneuvers *are* martial in nature in that they're learned through physical training, and using them well requires good physical stats.
6.ToB characters are more 'average' than their core counterparts. An unoptimized ToB character will be more powerful than a unoptimized core melee would. They're also more 'full' characters, having abilities that work outside combat as well, where-as your core fighter's best shot is Intimidate. On the high end, they're still only tier 3, compared to the full-caster's general lock on the two highest tiers(To present, I know of only one non-full caster to break their ranks, and that's Artificer).
Read the ToS ban list. If you're players mention anything on that list, be concerned. Some of it is cheese-on-sight(such as Pazuzu), while other things need a bit more effort to break(Like Nightsticks). Ban the former, and hopefully house-rule the latter, preferably where the problems are.