Flower Gem tips
1.Never ever use Flower Gems to restore raid or stamina points, those things regen on their own.
2.Expanding your knight roster will happen more often than your equipment list since dragons and fairies occupy the same space as your knights. As long as you have enough space for your equipment, you really don't need much more.
3.Wait for 50 gems for the 11 for 50 special.(Or at least wait for the limited gacha) Premium gacha doesn't look to be worth it
Given the difficulty of obtaining one from gachas, is it better for a rare knight (e.g. rainbow, gold) to get an immediate upgrade instead of being stashed while waiting for copies?
For silvers and golds, it might be better to wait until you evolve them back to level 1 so you can save yourself a few coins, otherwise upgrading them along with other manyus immediately is not bad either. Also for rainbows, up to yourself, most would want to keep copies of the same, especially if you are a f2p.