Kill Team, The Challenge

My local gaming club is going to run some Kill Team games this coming Sunday so I thought it would be nice to get some short games in. I'm thinking about a Space Marine list but I'm not sure what to pick.
The rules are;
200 Points
Units:
0-1 Elite
0-2 Troops
0-1 Fast Attack

Deployment:
Spearhead, Seize the initiative

I have never played this before so I'm struggling a bit to come up with a competitive list. Any help is welcome.

I also thought it would be nice to field my Orks army. I only have 5 Nobz and a gretchin unit which together is 200 points so that will be fun to play in a little game. It's not going to be a tournament but just some short games over the day so people can play with different lists and armies. I don't think 5 nobs and 10 gretchin with Runtherd will have much of a chance but it's all about having fun.

Click to enlarge

It will be great to get the Orky feeling going and let everyone in my club know I'm starting a Waaagh. The only problem is that 4 out of my 5 Nobz are still not assembled and largely unpainted. So this week I set myself a goal of painting up the remaining 4 Orks. When you look at the picture you can see that I have started painting them a bit already but they are far from finished and I will be struggling for hobby time this week, that in combination with my desire for high detail will make it a real challenge to get them done in time.

Seb