I've been experimenting with my Corrin and feel that if he had a +SPD -HP IV and change Fury to Life and Death 3, he'd be a monster with this skillset, he'd be hitting 45 Speed on initiation with a Speed Sacred Seal. He'd be doubling most of the units in the game without any buffs to their stats.
I'd like to think that Corrin is lot better than people make him out to be.
At first sight, I can only tell you it does seem to be the case. I actually got one, just yesterday. Also +Spd, but sadly -Def. First thing I had in mind is exactly what you do. One of L&D or Fury, and he's beasting an easy 40+ Spd and 50+ Atk.
We need more quick and powerful well-rounded male Lords, like the likes of Marth and maybe Roy. He seems to be this.
He's (in my opinion, at least) a very good sword unit. His main problem is that he is overshadowed by a lot of the other sword units in the meta, such as Ryoma or Lucina. If you run a LnD/Swordbreaker Build (assumed neutral IVs) he ORKO's 94 characters, Including hector. He's a good choice if you don't have the meta sword users, but he simply cannot outdo them.
Male Corrin is a more balanced sword fighter than most units. His abilities he has to start out are heavily lackluster. Why Obstruct is a thing is, well, beyond me really. He also relies on initiation, which will make L&D a riskier option for him.
If it's possible you come across another Corrin, I'd think he would still wanna keep the Resistance Bane that you have. That 3 HP could personally make a difference against one on one fights since his defense will still help him fair in one on one physical combat. Corrin should never be near a mage anyway, and If he does inherit Life and Death, he needs to scram unless you know you can initiate and win and have someone help him escape. Mages are common, so he may fall pretty easily.
Corrin's defense is good, so you could very well rely on that stat if you had Fire Boost or Swift Sparrow. His HP pool is pretty good, so he could make good use of those two abilities. Just a suggestion.
If the Corrin you have now inherits L&D, his resistance will be 16 (19 Neutral and 22 plus, which is still astronomically poor). Mages will tear him apart if you aren't careful.
You don't want to butcher his decent defense stats so running Swift Sparrow 2 is a much safer option since on the offense he gains 4/8 during initiation (4 speed from swift sparrow 2 and 4 from his built in Darting Blow 2 from Yato).
Life and Death isn't a bad choice since it boosts his offense tremendously, given that if he's +spd -def since his defense goes to a low 24.
Fury 3 is another solid choice because he has the bulk to stomach its recoil. Running Desperation on him is a must in my opinion rather than Swordbreaker.
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