If he’s made fast, he’d be a better version of M. Lepus lol. Bulkier and with no defense ailment downside.
I like the idea of just tweaking Thorne’s stats a bit more. Give him more oomph at the cost of less defense.
But in my opinion, I think Thorne is a decent hero already. Not amazing but he’s okay.
There’s other 5* heroes I’d pick first who I deserve an adjustment more (Khaghan comes to mind).