Evolution, despite being Swift, is much less useful than Scepter of evolution.
1. It's rare, so you can't rely on it. Auxilia, Second chance, Scepter of evolution are uncommon, Wish is common - these cards are much more reliable, especially when Wish is combined with any of these.
2. Scepter of evolution is expensive, but it makes hand better in 95% of cases. Auxilia doesn't guarantee better hand, but can hold a card in hand - rare, for example. Second chance is very random, but very cheap as well. Evolution doesn't have any of these options.
3. In some cases you can actually make opponent's hand BETTER for your own resources. Of course, it's not the case when he has Bahamut and 75R to play it, but when his hand consists of 8 commons, his chances to get better hand after your Evolution are very high.
I think that Evolution at least shouldn't discard another rares from your hand. That would be enough, I guess. Plus it would remove that countersynergy between Evolution and Globe of Myr.