Alright. Then let's see... Houndour and Rattata serve largely the same role statistically speaking, except that Houndour is powerful in special attacks and Rattata is better at physical ones. Both are fast and strong, but somewhat frail. Your Elgyem, meanwhile, is balanced in most areas, but somewhat slow in exchange for special attack power.

So we have an obvious leaning in your team's specialization already. The question is, do you want to try to balance that out, or pursue it? Both strategies are legitimate.