Even though calculating how much old mod worth in term of kudosu and coming up with prizes and prices for them can be tough, I still think that the idea of trading kudosu for rewards is interesting, and necessary. Standard doesn't really have this problem as far as I have seen on the modding forum, but for other modes, getting mods for the mappers' maps can be tedious and really hard, mostly because there is hardly any active queue in the forum.
Take mania as an example, being the 2nd biggest mode in the game, but people are still struggling to get mods. As seen in the survey in
this thread, the second biggest reason why mania only have like a few maps ranked per week, or even at the hardest time, none, is because mappers, both regular and new, can't get enough mods. The lack of modding queues for mania is at an alarming level, for as at the moment that I'm writing this,
there is literally no opened mania queue on the first page, and on the second page,
there is one normal mania queue with 1 M4M queue and 2 more hitsounding queue.
Quoting myself from
here, as a modder myself for 3 years, and also after talking to many people who have been modding before, getting too many requests really affect us modders. It is pretty much a common thing for modders to get burnt out when receiving tons of requests every time you open your queue, and the fact that the whole modding thing is a charity work doesn’t really give us that much motivation, even though we want to help others too. And I definitely think that adding this option or something related to it can helps this situation immensely.