Out of curiosity why aren't you racing this season? We're just getting started, you should jump into some crits! I got dropped on my first road race but I had great luck with crits, only been dropped on a crit that was a stage III race. I'm sure you're strong enough to hang on in crits, if I could do it anyone could.

I'm still new to all this stuff but I would say train on what you race on and don't worry about the weight, when I line up for a crit my bike typically is weighing in at about 19 lbs. Anywho crits are amazing training, I just finished my 10th race in the 5's and I'd personally say don't take 5's too seriously don't worry about being a super strong 5 just get out there while you're motivated.

That's my 2 cents.