As far as giving Vendettas HB's, I said that simply because it's a better buy than EA. You could leave them off like you have with this latest list though, but 10 pts (not 20) for 2 HB's is actually a good deal, and because of the way it moves and fires its weaponry you will get to shoot them if you want.
Still, it comes down to what else you can spend the 60 points on..you have a lot of anti-armour already, do you need the Exterminator rather than an anti-infantry tank?
Only you know the answer, but the top 3 Russes (not in order) are the LRBT, Demolisher and the Executioner, Exterminator would be 4th. The Exterminator is also the best Tank to give to Pask..you have the points.
You might as well give the CCS their 4th SW as well, no point wasting a slot.