Combat is based off of LoR system, but out of combat necessary optimization is lower and in-combat choices more streamlined, overall making the game more approachable - a lot of strategy will still be needed into harder stages though, with a ton of depth for those loving to optimize.
Although many parts of the game follow a fairly standard modern gatcha setup, you can actually completely ignore it for main story progression and play it like a traditional game, and overall it is significantly friendlier than most all other ones to players.
The gatcha system is basically completely optional for main story progression, as you get a base version (identity) of all characters and a base ultimate equipment (Ego) that are actually well-balanced with some strong highlights, easily capable of clearing all content so far. Thse base identities are also limit breaked for free as you progress in story.
You can also basically ignore the stamina system too. It's again optional for main story progression, especially using base identities, so you can just play whenever you want in that case. Sticking to using mostly base identities/the same identities means very little resources are needed, with what is incidentally tossed your way as you play being enough.
The leveling/limit break system for building additional characters using a stamina/daily dungeon system for materials, but XP cards and an excess of bankable stamina mean it's mostly a non-issue. You get more stamina than you need, and the farming stages (will soon next patch/already) cost E-boxes which you convert stamina to and can bank forever - you can just log in average 1-2 times per day, dump stamina into E boxes, and play when you have time; then dump resources to max out an identity you decide to build.
Gatcha just gives different versions (identities) that optionally replace the base identity and some different ego equipment for variety of gameplay (they are sidegrades, no *strict* upgrades for the most part) and some additional side story snippets. Characters and enemies have defined strengths and weaknesses you must account for anyways so you can't just sweep with one fixed team and definitely not one character.
On the gatcha itself, you get a fair bit of rolls and a newbie banner with some guarantees right off the bat. Identity rates and pull costs with the cheapest bundles are okay compared to most. Egos can come from gatcha, but rates are extremely low, so most come from a battle pass; free one gives half of the set, and afaik a fair half too in strength. Once an identity or ego is pulled, that's it, no more dupes necessary - that insteads fits into the pity system with shards. A fair number of shards are also farmable through a weekly dungeon. Although gaining shards either way is slow, it lets you select any gatcha character/ego you want in the end, including all newly released characters. These shards can also be converted to thread, the limit break material, but is not necessary for that either.