Do you think bike frame size is less important these days?

I've generally suggested a fitting if you can afford it and DIY if you cannot.
Get a rule of thumb setup and start modifying variables one at a time noting the effects. Continue.

• lots and lots
  
  

1) Buy a bike book with a bike fit chapter;
2) Measure yourself;
3) Work out sizings from book + measurements;
4) Ride some - feels wrong?
5) Ride some more - still feels wrong = tweak
6) go back to step 4

I think it was Hippy who mentioned, on here, about taking allen keys on rides. To make adjustment while they're still fresh in you mind.

Bloody good advice if you ask me.