I think both are awesome, but both are inherently different. Logan is about a man losing what he knows--the limitless ruperative powers of youth and who we are from those formative experiences--and coming to grips with this loss. In doing so, Logan, interestingly enough, get in touch with his own humanity in a way that could never be afforded by his unfeeling invincibility. In this way, Logan is like a man realizing he is past middle age and coming to some greater realization about the big picture of our existence.
Deadpool is the beginning of that life cycle and discovering one's identity in this big wide world (for Wade, this is a world in which he is a mutant and, and such experiences life in a whole new way). Wade's story is about self-discovery and a journey toward one's potential and what this means for their identity. In this way, Wade--and the humor injected in the film--has a frivolous, cavalier attitude about life, much like a young man, struck with the sense of invincibility, figuring out his limits in the world. Logan has been there done that, and now lost it.
They would be a neat pair to observe as they each sit at opposite ends of a park bench.
What they both have in common is a "new frontier," of sorts,as Logan doesn't t know how to exist in a world where he is slowly crumbling. Literally, everything from which the Logan we know derives his confidence has betrayed him. Wade is finding confidence in new strength.
Both are great, but I'm a sucker for sombre stories about the old dogs who struggle to hold on to what they have, so ai'm going to back Logan on this one.