Ouch, don't remind me of Disney Heroes... Still mad that EVE was a "Premium" character with no way of getting her beside forking over for the loot boxes.

Dragalia Lost is pretty good with the microtransactions. You get a ton of free characters, and your first character is guaranteed to be a rare one,but all the more common characters are useable, and even better in some cases. Plus, the only multiplayer is co-op, so having a stronger/rarer character is only needed in the super end game bonus boss stuff.

Fire Emblem Heroes on the other hand... Well, at least they're removing the earliest 5*s from the pool for new characters, so that's a start.
PVP? Check. Less than 3% chance of getting the character you want at the best of times? Check. Each summon costs around Ł2? Check. Need 11! of said character to get them to full power, not to mention certain other 5*s to trade over abilies from? Check.
Most consistant FTP way of getting new characters? Doing well in the PVP mode. -_-