What's a weapon you wish was better?

Always frustrating to discover a new weapon that I really like the design and usage of -- only to gradually realize it's a pretty meh weapon on the whole.

I'm thinking of the Alternox here, for my part atm -- love the design, the alternate fire, the electricity focus -- but it's not really all that good compared to any number of other primary weapons. I wish it was better!

What are some of yours?