Fighting STAB - 
cross chop - it seems fit for a floating mummy, also Close combat is viable, but will be sort of broken on this guy if you factor in the typing.
close combat
superpower
hammer arm - I would also suggest it somehow learn hammer arm as well, but it won't be the MAIN fighting move, just an alternative.
dynamicpunch
 
Which, if any, of the elemmental punches, should it have?
Ice punch
thunderpunch
fire punch
Broken indeed, but ice punch on something as cold (in more ways than one) as a mummy makes sense, and is sceptile and noir learn tpunch, I don't see why syclant cannot.
 
Should it get a healing move outside of rest?
 
Absolutley, as so many ghosts get acces to pain split, I think he syclant should as well, and moonlight fits his theme as well. Recover, not really, as it would be far too broken, and I don't see all to many mummies regenerating in the movies. On a side note, rest/shed skin would be halarious.
 
Should it get willowisp?
 
Yes, if sheddy can, he can. Also, all ghosts aside from froslass get acces to it, and most tanks (If I assume correctly that syclant is one), need some sort of really good support/status, this fits it really well.
 
EDIT- I would suggest hyper voice off the movepool. Otherwise, looks good