I do think that it is to wargear heavy as your Harlequin numbers are very small for a 1500pts. You have 19 'normal' harlequins, I have 21 in a 1000pts army... but thats me.
Ok now you HQ--
First what army are you vsing, that would help.. is it possible just to field a shadowseer or just a great harlequin if so that would save alot of points. However by looking at your low numbers and no transport the shadowseer is a must. Also the Shadowseer will be more than likely joining a squad and it would be better to include a differnt grenade ie. tanglefoot because of the dreadmask or no grenade at all.
I think myself that a soiltaire with that much wargear has a marked himself/herself with 'SHOOT ME' but hey that might be your plan but if you can litmate the wargear you could get more harlequins or some transport....
Your Death Jesters dont need the phase fields and mybe one should have a ELM because it has a ordance, however one could have a phasefield and could speed up a flank and bust the side armour of a tank.
Ok OK little numbers can break easily and preform bad in combat, yes sml number preform badly in combat with marines because you dont have enough attacks to punch through the 3+ armour.. so my suggestion is to pump one up to 7 or 8 and the unit could include your shadowseer to protect in from fire. If your buying a mimic just for the extra H-kiss then just give it to a normal mime because it cost less( i think
Ok you need at lest 1 venom and this should include your soiltaire. The mimes should flank one side but the venom should be right behind them just to back them up...
I hope that help.