The idea in general is good. Instead of buying xp directly you could buy a multi for gold.
For example + X1 for 60 minutes for 50k (thats a random number), also you have to take in account that this would bring 60 x 50 gold = 3000 gold so the total price would be 47k for a total of 60 x XP tick where 1 tick goes from 1000XP up to 1450XP (Gen16 I believe...?). So that would make something between 60k XP up to 87k XP.
of course it cannot be higher than x5... a bit risky then to buy multi, especially for good people cuz good players make multi

maybe bullcrap. maybe not