I'll just throw in another few plugs for Martial Combat,
One not-widely-known perk to Ki Push is the fact that it's a short duration Mag 4 hold, so it will hold bosses with one application for a couple seconds. Basically, the hold lasts for the repel portion (where the mob is flying back in slow-mo, legs flailing). While that's not amazing as a hold per se, it is incredibly useful for detoggling mobs, or delaying them long enough to put them down before they fire a power - things like Masters of Madness (detoggling their psi armor), Dark Ring Mistresses (detoggling Darkest Night), Paragon Protectors (preventing them from firing MoG/Unstop or firing a nuke), Master Ills (preventing them from phasing). A fast-activating one-shot boss hold is amazingly useful on a blaster! It also does respectable damage if slotted for it, but I wouldn't make slotting it my highest priority. I would put a dmg in it before a knockback enhancer, personally. I find the base repel+knockback is of perfectly adequate distance to create space (especially with Reaction Time slowing a mob's return to melee distance). My Ki Push is one-slotted with a +5 Hecatomb Dmg, but I have decent +acc and +rech global bonuses. YMMV.
Storm Kick has a 100% chance of knockdown (assuming no KB resists). It activates very fast and recharges quickly (and does good damage) Like Ki Push, it's also great for preventing mobs from activating annoying powers. I use it all the time for preventing Fake Nems from activating PFF.
Eagle's Claw is one of my overall favorite powers across any set. First and foremost, it hits like a freaking truck. It's a 100% mag 3 stun, so it can take up to Lt. rank out of the fight for a few. And perhaps most importantly, it's stylish as hell, with a very satisfying "Pow!" sound when it connects.
Dragon's Tail does decent Melee AoE dmg (more AoE is a always appreciated), and it has a 75% chance of knockdown. Like most of the /MA powers, It also activates pretty fast.
Burst of Speed is great for the element of surprise. If you have the slots for it, it does decent (not amazing) AoE damage as an opener. When used to jump into a large group, it has pretty high odds of activating Reach for the Limit's +dmg/+tohit buff for your next few powers. I have the full Superior Avalanche set in it primarily for the enhancements and bonuses. I thought the Chance for KD proc would be really useful when opening a fight, given the long listed recharge of the power, but I think the really short recharge for the first three uses skews the proc rate (the long recharge only comes into play after three rapid uses) The KD proc fires here and there, but not enough to be a reliable soft control as a fight opener.
Reaction Time slotted for a bit of slow is really nice mitigation. Obviously it hinders mobs from closing to melee distance. But it also seems that heavily slowed mobs freak out a bit and will spend a fair amount of time trying to flee rather than shooting at/punching you. Mine is 5-slotted with Miracle for the +absorb and the endurance proc, with a single generic +5 slow IO as the sixth slot. At lvl 50 it gets me 217 hp of fast-replenishing absorb.
I find /MC is a great combo of fast-activating soft/hard controls and damage, plus a bunch of stylish flair. I really, really, really love my DP/MC for the great animations, varied damage types, and controls. And built for defense she is a bit of a steamroller.
One caveat: My DP/MC has been lvl 50 and kitted out for a long time, so my memory of her effectiveness during the leveling process is faint. I do not recall having meaningful problems leveling her, though.
Give it a try!