Sub 3hr Marathon Training with TrainerRoad

Hi

Having read the thread it seems you guys are all very capable runs so I thought I might ask for some tips. I found myself constantly switching between plans run slow, spend time in z4, cross train on the bike , stay out of the gym, I am always think oh maybe that would be better. My story is that during the London marathon 2018 I broke my leg at mile 16 but managed to hop to mile 24 where it just give up on me. I have now return to running and cycling and have “lucky” got a place in the 2020 marathon. I have been running around 15 to 20 miles a week and also sort following TR build plans with some success and a little cross in the gym. I have been trying to do 1 hard fast run, one long run and one speed work session and have improved my pace. Do I just carry as I am or would following a dedicated plan by somebody Jack Daniels and Greg Mcmillin and what ever google gives me.

As I write this I am not sure what I am after advice or reassurance that i am on the right road.

Thanks guys