I like the way the system is now, and to hear from skinz that his maxed seraph 5 is 500 gems for a saint removal seems fair to me. Considering only 1 person in the game has reached this point, it won't be reached by most of the player base.

The stronger you are the more it costs, that is the way all these games work.
You don't complain about the costs of upgrades going up as you progress, or the cooldown timers getting longer.

So I fail to see a valid argument apart from one that 'I would prefer it for my convenience to be this way.'
It is a marked improvement over what we have had.