Yeah, Leon is boring. I guess he kinda stood out when put together next to other (horrible) capture targets in the game timeline. The thing is, in this timeline they won't grow up to be horrible at all, so they will all be essentially just as "nice" and "kind" as he is, along with being extremely devoted to the MC.
Leon will still be much, much older though. And yeah, it bothers me as well.
I read the novel a bit, but even then it's a hopeless harem/Mary Sure sim where the heroine is ridiculously perfect all the way, and while everybody falls for her, she's just to dense to notice. I took my share of pleasure reading it, I suppose... but looking back I can't help but think it was all kind of pointless.