gameplay do give fft feel and tagatame, which is good combination. lots of features despite being standard one. small improvement can be made with the ai and some functions such as buff/debuff timer, auto repeat quest x times etc
monetization however... well it's the usual gumi monetization. your characters progression will get blocked by that crystal wall sooner or later. keep in mind it's NOT you MUST pay real money, you can try with freebies but it WILL take time. they also add royal rank which progress faster if you pay. kinda bummer.
all in all if you are not into pvp, you can enjoy th game as filler or time killer. but if you are min max-er or pvp-er, well... how tough your wallet?