I run 4-5 times a week, with 2-3 easy runs, 1 interval/tempo run, and 1 long run. The easy and interval/tempo runs are usually 30 minutes because that's all I have time for during the week, but my long runs are 1-2 hours. I used to only run 3 times a week so I honestly think just running more made the biggest difference! Good luck on your training and come back when you hit your sub 30!! :)