Honestly there's potential, because they are giving him 'every useless skill'.
So this can go two ways. Either they will just say 'well that combination of skill makes you immortal accidentally' or the hero will actually put some thought into making them work.
There's one manga that does this,Toaru Ossan no VRMMO. Since he just wanted to have fun, he took skills that people considered to be the weakest, and honed them in ways the other players hadn't thought about. If that's the path they go with, then this manga might be interesting. But if everything just falls into his lap, then no, we've seen that before.