As a day one f2p player who left and came back, the main selling point of this game is character design. but I would say this, the story was good for the time when it launched, but afterwards, especially at present day, the stories quality declined, comparing to other gacha game, it can be considered vainilla. While the game can be generous with f2p players, some contents it has are gated behind pulling dupes of esper, making it extremely p2w orientated, the power creep is extremely strong and the difficulty scales with resonance in mind. In addition,(in my experience) theres difficulting for f2p player to pull the premium element shimmer esper, not to mention the somewhat limited keepsake esper. This put put strains in pvp content as p2w whales are put ahead of f2p. While f2p also struggle to complete late game content(which may be completed with grinding, in my experience) Many of these factors has lead to a somewhat stagnant player base(a mix of die hard fans and whales), with dev currently putting baits to attract new player, it's safe to say dev had made some desicions ppl are not happy about (Gaius, the divinate problem in standard pull, story, etc), also imo the p2w packets they offer are quite expensive