Make a budget, buy gear, and then spend the rest on a bike. Better gear not only makes you safer (to a point) but also more comfortable.

My bike is an older sport tourer that will do 70 in first gear. It's very fun, but I went back and did an MSF refresher course and had a ton of fun on the little MT03s they had. I wouldn't want to do a cross-country ride on them, but they're fun little commuters you can really wring out and use the whole bike at legal speeds.

Having a fast bike is a lot of fun, but it's very much a "with great power" kind of situation. Even a moderately fast bike is faster than any car you will ever drive, and little mistakes can become big ones really fast.

None of this is meant to scare you, but you'll have a lot more fun mastering a small bike and moving up than you will being terrified of ever really using your bike.