I am currently up to the last battle of Hard mode story. Plot battles have started getting pleasantly challenging which is nice. It would be cool if the stamina costs were somewhat lower but you get what you pay for. Besides, it really makes you want to think things through carefully, thus replicating some of the tension of later turns in an FE battle in a rather different setting.
Unit notes:
Lyn - Lyn is my only five-star unit, unshockingly she is good. Get her below half HP and she ruins anything she doubles (which is most things... but not everything) once she's below half HP and her followup attacks come before enemy counters + she gets a large attack boost. Oh and she passively buffs adjacent ally speed which is neat for getting over some key benchmarks.
Awakening!Tiki - Range 1-2 counter, great atk/def (manaketes doing magic damage is kinda weird but hey it fills a range 1 magic niche). She's pretty excellent except that she gets destroyed by non-green mages, especially ones with speed, because she's rather slow.
F!Corrin - I have blues now, it is great. Corrin specialises in tilting stats, ALL of them. Seal Res (mostly just helps her own damage, but nice with mage support), Hone Attack, but the real star is Dark Breath's massive AoE atk/spd debuff to all nearby enemies, doesn't even need a limit gauge to work. Stats are respectable all-around with res being the only real issue (but unlike Tiki her speed is fine). No range 1-2 counter but you can't have everything.
Clarine - Heals and has 3 move. I don't have much to say about her but being 3 move helps so much with flexibility. She has a limit which buffs speed on a heal but since none of her healing is that strong I tend to stick with Imbue to get periodic healing which is actually -good-. The tradeoff between Reconcile (7 healing to self and target) vs. Martyr (heals target by 7 + half of Clarine's lost HP, heals self by half of lost HP; adds +1 to limit time) is tricky. I like that she's fast/bulky enough (mostly against res but her def isn't a joke like some) to take the odd hit since that charges her limit and spreads out damage for healing.
Catria - Fast-charging Luna, flies. Overall I like her less than my core party when flight isn't on the table, but she's still pretty good and flight is just amazing on some maps. I didn't have any fliers early and that sucked because they help so much sometimes, even without the extra move they enjoy in most FE games. (FEH striving for balance kinda soft-confirms that fliers are OP in most FEs.) Seal Attack and Armoured Blow are nice.
Arthur - Lance units gonna die. Emerald Axe doubles offensive weapon triangle effects, Lancebreaker means he doubles and they don't. Against everyone else he's got a lot of HP but the speed could definitely be better... he's really only useful if the enemy has blues, but he's pretty good even against the mages for hitting them so hard (e.g. Masked Man).
Nino - Only 3* I'm still using, Nino has a lot of cool toys like Hone Atk and Draw Back, as well as making others' stat buffs on her more effective (hi Corrin) and she's better at baiting mages than Tiki is, though way worse against physicals because she's made of paper. I may up her to 4 at some point, though I do have a 4* Merric I could level up, and Cecilia's also an interesting choice for that green mage slot.
Palla - Another 3* I have reasonably high, though has now fallen back of my main team. Again, flight is good. She also has Spur Speed and her stats are respectable/balanced. Part of me wants to upgrade her for Goad Flyers and see what monster that makes Catria.
Hana and M!Corrin - Two perfectly respectable sword infantry units who I benched hard as soon as I got Lyn, because yeah no. Corrin's even 4*, it doesn't matter. Obstruct seems kinda trashy. Hana has Armourslayer but I've got enough magic damage (including red in Tiki) to not worry.
Oboro and Sharena - Back in the dark days these were my best blue units. Sharena is fine, Rally Attack was nice but these days having Hone Attack flying around devalues it a lot. Oboro has armourslaying and Seal Def but her stat build definitely stopped being competitive after a good start (hi RNG?), dat speed.
Beruka - I like Beruka and flight is nice but she has huge weaknesses in speed/res which make her pretty situational. She's solid as long as there aren't too many archers or mages around, though; her def is extremely good for a non-armour.
