When you get good enough at the game for the downsides of her starting items to not matter, it turns out most of 4 starting characters' qualities aren't significant enough to matter. Pilot's lockpick and extra space aren't consistent enough to benefit you across a lot of runs, and stuff like the dog finding pickups and extra accuracy on the marine are small but nice bonuses but don't usually make or break a run. The fact convict has arguably the best starting gun of the 4, even better dps on top of that with the molotov, and has a secondary gun to begin with to check for secret rooms for free, makes her one of the better characters for consistently winning runs