Words of someone who is yet to give Shamir their virginity.
Lances have best weapon arts AND the best weapons by far. They only lose to bows because they make you work to reach Hunter's Volley levels of stupidity.
I find rapiers to be kinda cheat weapons because you can only get 2 through normal play (i think you can buy one normally and get another via paralogue), but you can shop early for 3 of those things if you DLC shop (which i usually do, since they cost quite a bit of renown early on). If we count rapiers then swords own lances and axes, if we dont then yeah they suck.
Ashiya is a meme weapon though. Thunderbrand is like second best weapon in the game.
No offense, but this is unreasonable-amount-of-investment wall of cope. On Lunatic, you would have to tolerate Raphs garbage early game, feed him EXP to get him to 30 early, tutor him to hit both War Master and Wyvern Lord, then max out War Master, then spec him into Wyvern Lord which is not even that tanky a class to rely on a enemy-phase talent on a unit who will take higher than 0 damage from the enemy.
By the time you are done 75% of the game is cleared, Raph is not Constance who's halfway through to level 50 before timeskip hits.
I'm not gonna deny that it would work or anything, but thats copium.
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On the topic of gauntlets, they dont survive frog litmus test.
Out of all weapon types, Byleth was the worst with gauntlets. After that run only Flayn is allowed to use them.