You should probably at least quote the text of the adaptation section that make you believe certain things about the ASS's maneuvers/spells.
If you prefer, you could instead emphasize the magical talents of the swordsage by giving the swordsage the ability to learn arcane spells in place of maneuvers of equivalent level. In general, spells from the schools of abjuration, evocation, and transmutation are most appropriate for a swordsage of this type, especially spells with a range of personal or touch. The arcane spell is “cast” as if it were a martial maneuver. In this case, you should remove the class’s light armor proficiency and reduce the swordsage’s Hit Die to d6.
So from this we can glean a few things.
- They don't get maneuvers. Instead, they get arcane spells of the same level that the maneuver would be.
- They don't necessarily have to choose from any list in particular, as long as the spell in question is available in arcane form.
- Abjuration, Evocation, or Transmutation would be the best schools for an ASS to choose spells from, but there could be exceptions.
- Spells with a Personal or Touch range should be emphasized, but, again, there could be exceptions.
- You don't actually cast spells. You initiate them, as if they were a maneuver. What this means for CL, Spell Resistance, or caster PrCs is entirely unclear.
It's important to note that Stances
are not maneuvers (ToB pg 43), but count as maneuvers for the purposes of fulfilling prerequisites for higher-level maneuvers or qualifying for prestige classes or feats. Since the ASS only explicitly gives up maneuvers, he keeps his Stance progression (though he'll probably have a hard time meeting prerequisites for higher-level stances). Since we're already deep in houserule territory to even consider playing an ASS, it would not be unreasonable to say ASSes don't get stances at all, or to allow an ASS to cast long-duration personal spells as if they were stances.
This next part is definitely going to be controversial, but it's worth thinking about. The second-to-last sentence says "The arcane spell is “cast” as if it were a martial maneuver." Personally, I believe that means that you don't actually
cast spells, the author just used that as an analogy - that's why he put the word 'cast' in quotes. Instead, you
initiate spells, as if they were maneuvers. What that means is, you don't inherit the rules for casting spells, but rather the rules for initiating maneuvers. Your spells must be readied before they can be used, once used they are expended and cannot be re-used until recovered, they count as Ex abilities unless they're overtly magical (which they of course are), you don't have Arcane Spell Failure, and so on.
This raises the important question of CL vs IL, and that can't be easily answered. If you're not using the rules for casting spells, then you shouldn't use CL. But IL specifies that it equals your level in the class that provides access to martial maneuvers, which ASS does not (instead it provides access to spells, which are initiated as if they were maneuvers). By that logic, your IL for spells would be half your ASS levels. That's dumb and obviously not intended. I'd recommend going with the intent behind the IL scaling rules (spelled out in the first paragraph under Initiator Level on ToB 39). Maneuvers are intended to scale poorly since you can use them over and over, and that's why you get half IL for non-maneuver using classes. But, since you're picking spells instead of maneuvers, they scale at the same rate as spells. Based on that, you have two options for dealing with ASSes. Either treat their IL for spells as their full class level but don't count other classes as half, or rework their spells so that they don't scale as well. If you go with the latter option, take a look at psionics or the spell-point variant.
Next, you have to consider how to deal with ASSes and PrCs. Since they're not casters, they probably shouldn't qualify for caster PrCs, except maybe ones that require "ability to cast Spell X".
Finally, we have the question of which primary "casting" stat to use. The book gives absolutely no advice, and you could make an argument for any of the 3 mental stats, or even all of them at once. If you don't nerf their spells by un-scaling them, I'd suggest having each school use a different primary stat, much like different martial disciplines use different stats. I'd probably go with Abjuration using Int, Transmutation using Wis, and Evocation using Cha. If you did un-scale their spells, that's probably overkill and you should just pick one.
