For a beginner of the franchise and this style of game in general, I think it's rather just keeping with its gameplay affinities, it will enhance your abilities naturally and without discomfort. Choosing easy options for first play is definitely the best choice, even though you're a sucker of challenge, as it will allow you to focus more easily on multiple aspects of the game that you already know and appreciate, which is important when being confronted to a challenging game/challenging aspects of a game, to not be overwhelmed by adaptation of a new gameplay.
About equipment of your army and its management, you will tend to spam the "optimize" button each time you will begin a battle without much thinking I guess, and you will be more aware of what you use and for who by time and experience (you will maybe tend to a point where "optimizing" strictly for every soldier won't be possible, because short in items, weapon, and so on). The same goes about utility of stats cartel ; just judging by damage cost for allies and ennemies will be relatively sufficient at the very beginning, but not for long (you still can manage like this on easy sets I think, but I'm not so sure about that).
You honestly won't have to worry about selection of weapon and selection of pairs in a strategic way as something vital with this first play. This will be the opportunity to comprehend mechanics for a possible second play with another way of thinking/playing.
Management of your allies goes the same way. There are people like Ransu and myself who are just total suckers of these social aspects in games, and will tend to just go with personalities, bias, dumb otp, something that is totally fine and won't be an handicap while playing further (on easy sets at least), and that's what you will probably do at first if you're not at ease with stats profits. As well as you can be a sucker of social ships and still be conscious of being able to get the best of your allies, or just don't care about characters' relations and focus on abilities, or even don't care at all and randomly pair up everyone or a part.
About the amount of soldiers...well, it's only a little patience challenge if you envisage to max stats everyone. You can stick with a fair number of few of them, if it's your preference.
In a nutshell, in easy play, just enjoy the game in a relaxing climax, it's playable even for someone who is new in strategy game. Pairs, items, weapons, stats, class and sodliers selection are troublesome in more difficult sets. You will surely arrive at a moment in the game where you will feel at ease and you will pay more attention about those more technics aspects, at your speed. The game is enjoyable without thinking too much strategies, but yes, for a game with a main strategic axe gameplay, it will even more enjoyable when challenging.
Well, I don't know, maybe my speech is just totally dumb. I know how difficult chosing class for a character is damn difficult. The best way to not lose days to chose while not knowing what exactly you are doing is to define restrictions. Like, limit a mage to magic/support related classes, or things like that.
For items and weapon, you can pass through the game without going too much shopping and upgrading ; favorise cleaning maps to collect things.
About level up, in easy sets it's...well, easier to do with reeking box (cheapier). It can go pretty fast that way. For class, at least a thing to be sure to do is to not upgrade a character without a 15 -if impatient- to 20 level.
The main interest as you said of well thinking pairs is the child's stats that will come out of it. The child will get an ability from the father, and one from the mother (more or less randomly, even though there are some "tricks" to be sure to get the results you want). If you want some specifics abilities to be transmitted to the descendence, you can keep that in mind when pairing up.
All in all, don't be scared to try things in matching troops, pairs, classes, regardless what other said if you're not in a cul-de-sac; depending on your own mind will help you to elaborate the genius stratege in you ~
And I think there's more to say but I'm so done talking too much _
3」∠)_ I hope though it helped a bit.
