You have nothing to hit water types with for super effective damage, you have nothing to effectively inflict status with and 3 of your team members are weak to ground and water. What you need is a good grass type and I think the best one for your team would be Tangrowth. Tangrowth has acces to Sleep Powder and Leech Seed but you could also give it Toxic if you wanted to. On top of that it has great physical bulk which your team lacks and covers your weakness to ground and water of course.
If you want any other suggestions for your team, I suggest giving Ninetales Freeze Dry instead of Ice Beam to further cover your weakness to water and I would replace Tyranitar's Brick Break with Thunder Wave since you already have 2 other mons with fighting moves and you don't have a lot of status moves yet.
Hope this helps.