My team is Jirachi, Starmie, Salamence, Tyranitar, and Breloom, although I'm not sure about Breloom. Maybe Blissey instead. But that's for the RMT forum. Anyway, I don't think Metagross or Heatran would work well as that gives me a 3x Ground weakness. Also, I'm using Tyranitar with a Choice Band elsewhere on my team, so while I did consider it, I think that I would prefer death to all ghosts more than a sandstorm lead. Hippowdon is a good idea, but I don't think I need sandstorm at the start, especially as TTar already has it and it damages some of my pokes. Btw, do you think it's a bad idea having Sand Stream on the team when my sweepers are damaged by it? It probably is. I'll have to make some rearrangements. Anyway, Swampert or Gliscor (hadn't thought of him) would work well. Swampert could act as my TTar check, and Gliscor is really annoying in the sandstorm, as well as being a great all-around tank. So the choice for me is really between those two. Swampert can provide nice type coverage, but Starmie really takes his role. Gliscor is, I believe, the best for my team due to its tanking capabilities and Taunt.
EDIT: Sorry if this is too much like an RMT, if it is just tell me.