Long post here so bear with me
I coached 6 female runners who lined up at the recent Olympic Marathon Trials. 5 were "moms"
In order of PRs
36 y/o mother of 2, full time job. Ran D1 in college, PRs 1:15 1/2, 2:39 marathon PR, 2nd marathon trials for her
41 y/o mother of 4 full time job, Ran D1 in college, All American, one world XC team, PR 1:15 half, 2:40 marathon (at these trials) 4th trials appearance (10,00m x 2 and marathon x 2, with no appearance in 2016 (just had a baby)
27 y/o no children, full time job didn't run in college, marathon PR 2:42, 1st trials
35 y/o mother of 2, full time job, ran D2 in college, PR 2:44 , first trials
35 y/o mother of 1, styay at home, didn't run in college, didn't run in high school 2:43 PR, 1st trials
33 y/o mother of 2, full time job, ran D2 in college, PR 2:44, first trials
Here's the thing, each of these ladies had completely different buildups and plans. (two of them had different coaches when they run the trials)
All had an emphasis on strength runs (MP and tempos) but I had to focus on their strenghts , one has zero speed, like can barely break 5:45 for a mile (when we actually spent a summer training for a mile!!) but can run 6:10 pace forever.
I think you really have to find out your strengths and build on them. High mileage isn't always the answer, but for some it is!
All of these ladies were able to dedicate 6-7 days a week to running, only two ever ran farther than 20 miles for their long run.
You'll probably get a lot of different replies and ideas (and that's good) but that's because there really, in my opinion, is no perfect plan.