Well, the BCM allows me to (at the expense of a tiger claw maneuver) use all of my weapons in a standard attack, which is good for when I can't get a full attack. Also gives me full str bonus to my off-hand attacks as well (not much of a difference, since I only have 12 str), and removes the -2 penalty for off-hand weapons.
The sneak attack is only used because that is what is granted by assassin's stance, which I want to be in because I need a shadow hand stance to take shadow blade, and shadow blade gives me dex to damage, in this case +6.
Now, if I am not mistaken, being hidden only works on the first attack unless you render them flatfooted somehow. If I get a high miss chance and gloom razor, I could make it so that an enemy treats me as invisible for the rest of the round, assuming they attack me. Alternately, blinding or stunning works, dust of sneezing and choking would work if I could use it as a ranged attack, without hitting myself. Stunning fist would work, but that won't be possible until level 12, and at least according to uber, spellcasters get immune to crits quickly, but wouldn't that mean that sneak attack wouldn't do any damage to them? I'm honestly not sure what to do here, I guess I'll just go with what I have, sneak attack damage on the first hit each round (hide at the end of a move and then attack) and flank whenever possible, which should be easy with a 60 foot move speed in combat and a good modifier for tumble.
I'm not really sure what I want out of my swordsage levels just yet, I need to look more at all the schools available to me. I like the level 5 pounce maneuver from the tiger claw school, full attack at the end of a charge is good for starting off with a bang, and as a Thri-Kreen, I expect I could probably get some use out of the jumping maneuvers. I haven't looked at much that wasn't shadow hand or tiger claw, admittedly, but I expect that I will find some good stuff.
I changed the progression so it goes monhum2/sage1/ranger2/sage1/BCM3, that lets me get shadow blade at third level, if I take a 1st level shadow hand stance (probably island of blades, I already get concealment from my armor, so I don't need the child of shadows stance). If we are going to be playing without initiative (some people advocate it for PbP since it is easier to just say whoever posts first, goes first), I will drop improved initiative, but if we keep it, if I win initiative, my enemies will be flat-footed for that round, and +11 initiative ought to work towards that.
Updated feats:
Shaky [flaw]
Poor Reflexes [Flaw]
Darkstalker (From Flaw)
Combat Expertise (from flaw)
Deflect Arrows [free to thri-kreen]
Improved Initiative (MonHum)
Multi-Weapon Fighting (Ranger 2)
Martial Stance (9) (assassin's stance)
Weapon Finesse (1)
Shadow Blade (3)
Superior Unarmed Strike (6) (+4 to unarmed attack progression)
Weapon Focus (Tiger Claw)
Monk unarmed attack progression (swordsage unarmed variant)