I've never had the opportunity to spend those two tokens when i really needed it.

You can bet your ass that if i do get 2 matches within 15 minutes (had that twice last season, and so far once this season), they are both away - and the last one is for sure an important one (usually in knockout stages of CL, or a Cup match against better opponent).

So ye, a minimum of 30 minutes (from the END of last match) until the next one starts would be a nice change.