Miko is a weird character. When in a random group, he’s useful but not OP. However, in a party, if he coordinates with someone, he can just create an unstoppable duo. I’ve seen this with a Miko+Galilea combo and Miko+Montana. I mean, in a game we played last night we poured down the fire on Montana and he was just healing entirely too fast. Plus, Montana has plenty of inborn health regen and this Montana wisely chose to go the “heat” route so that meant he basically never stopped shooting.
It seems that Miko could use a reduction in heal power or maybe some kind of cooldown so he can’t just constantly keep healing someone. At his current rate of heal he can get somebody back up to full health in far too little time and combined with a decent partner, they create a team that cannot be killed.