Go ahead and give fixed a whirl. Sure, there's a learning curve, but you won't regret it. I haven't. Been riding fixed since 2000, and My knees are just fine. The "You're gonna blow your knees out!!!!" stuff seems to come from people who have never tried one. The Late Sheldon Brown rode fixed almost all the time, and until his MS got the better of him, his knees were also fine. (He's the one who I caught fixed fever from) There is nothing I like better than riding my fixie on a warm summer evening. It's almost like a state of light euphoria. That's the best way I can describe it.

I also do not participate in that "brakeless" garbage. I'll leave that for the 20-somethings. (Love being over 50!)

So, have I totally blown off geared bikes? No, not at all. If I want to go single speed, I do have the freewheel and If I need it, it's simply a matter of re-installing it.

46 x 17 gives you a gear of ≈73 inches. This might be a little high if you have really steep hills in your area.