The answer depends on how many other attacks you have. In fact its best to look at all the attacks your thinking of taking.
He will honor his words; he will definitely carry out his actions. What he promises he will fulfill. He does not care about his bodily self, putting his life and death aside to come forward for another's troubled besiegement. He does not boast about his ability, or shamelessly extol his own virtues. - Sima Qian.
I have, on my MA scrapper 4 attacks from MA (and BU as 5th power). Thunder kick, Storm kick, Crane kick and Eagle's claw are my 4 attacks and I dont have any gaps in attack chain 
I guess taking Crippling Kick instead of Thunder kick would do you ok. I preferred thunder kick because of the faster animation.
- @DSorrow - alts on Union and Freedom mostly -
Currently playing as Castigation on Freedom
My Katana/Inv Guide
Anyone who doesn't take truth seriously in small matters cannot be trusted in large ones either. -Einstein
Another thing I think that its better to know about is your secondary.
He will honor his words; he will definitely carry out his actions. What he promises he will fulfill. He does not care about his bodily self, putting his life and death aside to come forward for another's troubled besiegement. He does not boast about his ability, or shamelessly extol his own virtues. - Sima Qian.
I do feel a bit of a numpty for not saying what other powers I was planning on taking in its place. I'm just too used to WoW, where everybody has the same skills and cookie cutter builds ><
From that though, I gather it isn't entirely blasphemous to not take it, but it does seem to make life easier if you do.
Looking at my build, I think I might take thunder kick, just to make the first levels that little bit easier, and then I should know a bit more about the game, so will hopefully be able to apply some extra judgement there.
Thanks for the help though!
WARNING: BROKEN BUILD ALERT
Flitz is definitely not a cookie cutter build. I had a specific idea in mind so ended up taking Thunder kick, Cobra strike, Dragon's tail and Eagle's claw from MA plus Flurry from the speed pool, the Sands of Mu veteran award and Energy torrent from Body Mastery epic.
Flurry and Sands of Mu have long animations that many people dont like, but the animation is the main reason I took them.
CS, TK and Flurry all have a chance to disorient and DT and ET can knockdown, so plenty of soft control although they don't really work on bosses and AVs.
Despite the dodginess of the build, I still made it to 50 with Flitz and he still gets invited to teams when I play him.
UNION @Flitz 50, Lead Hose 50, Red Rag 50
DEFIANT Rose Bloodthorn 34
VIGILANCE Captain Caledonia 20 - Yeah, I made toons on the French server coz we only had 4 back then (might have to transfer/recreate them on one of the US servers)
..and many more!
Take it to start with if thats what you want, you can always do a respec trial and respec it out later.
I'd skip it, ma has way too much good stuff to bother with it tbh
Okay, I am pretty new to CoH, so don't crucify me if this is a really dumb idea, please.
I was just wondering if it would be okay to skip Thunder Kick, and still manage to avoid gaps in attack chains.
Thanks for any help/advice!