At this point, I'd just practise F2L like crazy.
If by advanced cross you mean that you can see where the cross pieces need to go in a matter of a few seconds, then good on you

.
Make sure you solve cross where it is easiest for you to look ahead to your F2L. Com
PLETEly plan all the moves for your cross so you don't need to focus on the cross pieces when solving them. This time will be spent looking ahead for the first F2L pair.
I started out with Dan Brown's method and didn't start speedsolving the cube until I was down to 35 seconds, still with the DB method. It wasn't until I got to 35 seconds that I switched to Fridrich. Lesson: if one can get speedy solves with a slower method, he can get faster with a faster method.
Sure, it'll take time. Practise like crazy. CRAZY.
What not to do:
Do NOT focus on the last layer at this point--that'll come easily to you after your F2L is fluid, solid, and virtually pauseless. Metronome it if necessary.
That's about it from me.
--Ranzha