Well for starters I think you should make a list of Pokemon that are already on that level range of 5-50 to then max them up so people don't give you Pokemon that you already have maxxed out. Anyways, I think you should start in type order, meaning that you should start by catching Bug type Pokemon such as the three Burmy forms, a male Burmy and one female Combee and one male Combee......there you go :D
:t354:TG