Recommendations for mapping keyboard hotkeys

My keyboard (Cloud9 ErgoTKL) has some extra hotkeys. Any recommendations for mapping them to something useful? It's a tenkeyless so doesn't have a backslash, hash or tilde key and I'd like to map those to some of them.

I'm aware there are a bunch of packages that can do this but haven't tried any yet. Just wondering if anyone here has used any of them for similar reasons and has any recommendations.