I honestly feel like 4 wins for 1 chest is fair already, considering anyone could just queue and play for free rewards. You don't require a team, any time investment, you could just straight up queue and fight random people, win and potentially get a reward worth millions. And you want to make it faster or easier?
Regular PvP requires you to have good Pokemon, actual strategy, and the knowledge to use your team properly, as well as knowing how to play against your opponents teams.
In Random PvP, I could get a random Dunsparce with Serene Grace and start destroying an opponent because they were unlucky with their Pokemon. Alot can get frustrated, and even you could be the frustated one, but that's all what Random is about. You're either lucky or unlucky.
Overall, in my opinion Random is way easier and doesn't require any changes to it.