I really like the Deathwatch models but I think they would look just that little better with a smidge of heresy.

So what I am thinking of doing is grabbing a killteam set and kitbashing it with the
CSM boxset and some
FW Legion upgrade sets (head and shoulder pad), I might even attempt some
GS sculpting for some things.
Now what I would like to ask all of you is if you have any suggestions for making the models look extra cool, so far I have decided on:
An Alpha Legion sniper with a stalker bolter, headhunters head,
AL pad and, maybe, a little cloak.
An Iron Warriors heavy weapons guy with a frag launcher,
IW head,
IW pad and, maybe, a servo arm.
A Night Lords
cc specialist with twin blades, terror pack head,
NL pad and, maybe, another cloak. (this one a skin cloak with severed heads attached

)
A Fallen Angel with duel pistols and a blackshields body. (Doubles up as a Cypher conversion if I need him)
I am a bit conflicted for the last watch member, I could go for:
A Deathguard specialist with a Meltagun, plague marine head, plague marine pad and, maybe, some decay.
A Word Bearers squad sergeant with a pistol and maul, squad leader head,
WB pad and, maybe, some scrolls.
A Black Legion squad sergeant with a pistol and sword, squad leader head and a
BL pad. (Couldn't think of any extras)
A Thousand Sons squad sergeant with a force staff, exalted sorceror head and
TS pad. (Kitbash with Exalted sorceror kit)
A World Eaters
cc specialist with duel maces, Khorne bezerker head,
WE pad and, maybe, some chains.
Or
An Emperor's Children
cc specialist with twin blades again,
EC head,
EC pad and, maybe, a doom siren.
So which legionary should I have as my 5th member? Any ideas for accessories, better parts or
GS mutations to use on my killteam members is also welcome!
(Currently leaning towards the Thousand Sons Sergeant, partly because I love the exalted sorceror models and partly just to hav a squad leader.)
Thanks.