Or perhaps you can do a per-game rental of any skin (currently purchasable, no legacy or limited edition). Pay an equal amount of IP for a skin's RP cost to use that skin for 1 game. So If a skin costs 975 RP, pay 975 IP. Or 260 IP for a 260 RP skin. People would be losing IP for every game they did this with, and it is an infinite IP drain.
Of course, you could tweak the numbers. Maybe double IP per RP, as some players have TONS of IP (150,000+ IP)
Let me do some math. Assuming 150,000 IP to start, and assuming ~60 IP per game on average (50 average + win of the days, low balled), and using a 975 IP rental skin every game: you'd get 915 net loss per game on average,, meaning the player would lose all their money in about 160 games. That seems fair to me, what do you guys think?
This would also allow players to effectively "try before you buy". Whether that's a good or bad thing is beyond me.