The Soliatire is awesome, definately worth going with. There's also the Pirahna but it's not as good. The Locust IIC is pretty handy.
Some long range weapons for support would be helpful, the Mad Cat II works but there are also mechs like the Warhammer IIC 4, Rifleman IIC, Rifleman IIC 4, Glass Spider, etc. Personally I'd pick any two of those.
With their trading connections the Sharks can (and do) get hold of just about anything, so you have a fairly free hand in what you use. There are very few Clan mechs that you can't justify being in a Shark Star.