IP to RP convert idea?

So i dont own all the champs but now that i have nothing left i care about buying my IP just sits there, so i now understand how everyone feels when they have all champs, runes, rune pages, etc. So i have an idea to make IP still worth something after all that is done, what if riot makes it to where you can convert 100 IP for 10 RP? Or something along those ratios, itd make it slow enough that people would still buy plenty of RP, especially newer players, but at a decent rate that people who've been playing for years and years and now own everything can still feel rewarded from it.