Going by First Win of the Day, 1 IP (BE) is worth 3.33 XP
500 Xp from first win (Early in the preseason) vs 150 IP (BE) Currently, it grants 400 XP and 50 BE for first win (so that small 50 BE is actually far above its value in XP) Alternatively, looking at it through the new first win system, 1 IP is equivalent to 4 XP (150 - 50; 500 - 100)
So going by the first, a typical game of Summoner's Rift, which granted ~60 IP on loss and 90 IP on win, should give 200XP on loss and 300 XP on win in the new system
Instead, it's about 130 XP on loss and 200 on win.
Raise the XP earn rate ffs. It's bad enough that with the diminishing returns of levels it takes more and more XP to get the same crap disenchanted to 800 BE. The lowered earn rate of the new resource on top of that is just plain insulting.