"chicken and egg" kinda confusion (account planners)

Hey,

I've recently started to research my career path (again).

I had an internship with ad agency abroad (I live in UK), and there I realised i am actually better at strategic planning than copywriting (which was my original aim).

Now i am back in UK, I'm looking into postgraduate/MBAs for account planners, strategic planers? Do you have any suggestions? (I have a BA in advertising)

Also there are a lot of suggestions for creatives on portfolio, networking etc.

But how do we planners get to do the same to get our foot through the door? I love generating ideas, and working closely with creatives. But as I'm not a creative (in the industry sense), how do i execute my ideas for strategic planning solutions/briefs? I never heard of a portfolio done by account planners, although aren't we full of ideas as well, and actually the ones giving the bullet points in briefing creatives? (USP for the brief etc)

I would love to have any kind of information on any of what I've written from people working in advertising, and preferably strategic planners.

Thank you for any insight you might provide.

cheers!
Nes