Grey Knights as Allies

I've been using my GK a lot lately and the other players in my FLGS seem to be watching me and trying to counter my regular list so I've been looking at ways to give it a twist just to throw people a little bit ( I'm having great success lately simply because people in my store haven't played GK before)
My current idea is to take a regular marine army with a HQ, two squads of troops with rhinos(mostly because i want to give them to my PAGK first turn) and a raider, then take most of my GK which is a fairly standard GK list (8 man squads with dual psycannons + dual dreads). The problem I'm having is a)Choosing an army to compliment my GK, and b) making them competitive.
My thoughts so far are:
1) Pedro Kantor - guy has a great storm bolter and the bonus attack could be a game changer considering GK are fairly CC capable
2)Lysander - Bolter drill could be very dangerous with GK's. Normally I argue against taking lysander specifically for that but he also adds a great counter punch to a unit that will allow it to hit an enemy hard when assault comes around, plus his 3+ invul and eternal warrior can help absorb blows that would splat GK's
3)Logan Grimnar - I've had great success a few times using Logan attached to some GKT, plus the SW stlye of mid range firepower will work really well with GK. Let the cheaper GH get closer to the enemy and screen the GK then allow the GK to counter assault and finish enemies off.

So what do you guys think of my idea? Which would work well of any? Are there any better choices? Am I an idiot and a heretic for even considering using other marines? Once I get some feedback i'll do up my list and post it for you guys to tear apart

Just remember when your using another army and allying GKs to them that you're limited to 1 HQ, 2 TR, 1 EL and 1 FA. No HS so that means you can't use dreads.

I've actually played around with the thought of adding an SM HQ and two Troops in Razorbacks on more than one occasion. Especially after every game where the lack of mobility really stood out and cost me bigtime. As Rivan said though, you'll have to draw the Raiders and Dreads from the SM dex. My loose fluff for the Grey Brethren were marines that could never quite attain the full psychic ability to become GK's but showed other qualities that made them too good to just throw away. They were kept under the Inquisition and led by a Librarian (keeping with the psychic fluff).

I was interested in doing similar with the BA codex.
Can get a cheap but nasty Lib as a HQ, and two scout squads or Assault squads with vehicles to give to the GK's for about 400 points all up.
The problem is your already losing a large chunk of your points.

as the current 'dex is limited been thinking about adding the following

termi chaplin
joins the GKGM and retinue for reroll goodness

2 X tac squads in r'back, sarj with fist + combi melta
sarj for anti armour, r'backs for PAGK's

vidicator
deadly short range gun compliments GK's

land raider
for GKGM to ride in