Synergy in a Melee Multiclass build

[Eorran]

I have a gestalt character (converted from 2nd to 3rd ed) in a campaign who is currently a Swashbuckler 3/ Fighter 4 / Duelist 1 // Spellthief 8.
The character is the "dashing young officer" type in a Renaissance-ish period campaign, though the party is travelling a long way from the pseudo-European homeland. (Currently in an Egyptian-style kingdom, will likely travel the world through the campaign)
I've found a mix of melee-types to suit him so far, and plan to take Duelist until level 4 at least (so I can get my max Intelligence to AC bonus). After that, I'm looking at Tome of Battle. However, I've only perused the book briefly, and come up with a challenge.
Swordsage seems to suit the build of the character (High Int, Dex, moderately high Cha. Uses light weapons with Finesse, combat style based on mobility, tumbling, etc.) but suffers from the slower attack bonus progression than Warblade.
Warblade, on the other hand, doesn't seem to have access to the mobility-oriented schools (can't remember which they are).
I'm looking for suggestions that will continue to enhance the character's melee ability, using the same combat style he currently employs.
(If anyone cares, on the Spellthief side I plan to multiclass to Rogue for more Sneak Attack and slightly better skill points.)
Thanks.

[Darrin]

Warblade, on the other hand, doesn't seem to have access to the mobility-oriented schools (can't remember which they are).

That depends on how you define mobility. If you mean Shadow Jaunt/Step/Blink, concealment, and air walk, then SwordSage is your only option, but that class uses Wis more than Int.

If you mean Sudden Leap, Death From Above, Absolute Steel, Press the Advantage, Bounding Assault, or Quicksilver Motion, that's quite a bit of mobility for a Warblade to choose from.

If you're using Swashbuckler to add your Int bonus to damage, then you'll probably get the most synergy with Warblade. Start with Tiger Claw for mobility and TWF, consider Diamond Mind later (Bounding Assault or Quicksilver Motion), and White Raven for coordinating with allies. Pick up Mountain Hammer from Stone Dragon but otherwise stay away from it.

[Azerian Kelimon]

If you're going to do the ToB, screw all that class mishmash you've got and go single class on swordsage or Warblade.

Now, your pick on which you should take is mostly based on the personality of your character, here. Is he upfront and confrontational? If so, a Warblade is much more fitting. Is he quieter and more prone to flexibility and out of the box solutions? If so, Swordsage is much better for Shadow Hand.

[Riffington]

As a minor point, you could theoretically have an issue with Spellthief because it's sort of a magic/thief class that Gestalt frowns upon.

If you are permitted to keep Spellthief despite this, it probably goes best with straight Warblade. The extra skill points and ninja-ness of the swordsage are wasted since you'll get that from the spellthief side. The high BAB and HP of the warblade are not at all wasted...

I have this horrible thought that Daring Outlaw could possibly make a gestalt swashbuckler insane... not sure of all the interactions there. Say you were Swashbuckler 8/Rogue 8, would you have 8 sneak attack dice? If you have Swashbuckler 8/Spellthief 8, would you have 4 sneak attack dice or 6?