If it stops me getting bored and keeps me heading out, that's a win. If I get faster as well, that's a win-win.
They say the best training plan is the one you actually stick to!
I'm a massive fan of parkrun. My 10k was very satisfying, and I still dream of doing 'proper' long stuff, but for those of us still paddling in the shallow end distance-wise - and if you have one local - I think they're superb. I look forward to the Thames retreating from our local course! I definitely find that having a scheduled event makes me less likely to shirk than my own personal flexi-schedule (I'm procrastinating as I type this
)
Pippa, I sincerely hope you're not
truly bothered by finishing toward the back end*. But given that you're clearly still on an up-curve, I'm sure that 33min will continue to drop, even with just a parkrun+2midweek runs, whatever the length/intensity. It's the reward for sticking at it - I'm convinced that just doing SOME miles every week is more important than having the scientifically best training plan!
*(parkrun is the first sporting event I've ever come close to the midfield in - I expect to be soundly thrashed whenever I play sports, and am often last in time-trials
(and audaxes). This is a strong indicator of how inclusive it is, and how many beginners take part. Someone has to be last, and every time I am, I save someone else from the honour.)