Thank you so much for all your replies. I’ve finally had a chance to sit down and read through them properly without getting distracted! It has been so interesting and helpful to read everyone’s viewpoints.
I was diagnosed with Autism 2 years ago and then additionally ADHD 1 year ago. Whilst the diagnosis’s have been a relief for me, in understanding why I struggle with the things I do, I feel it is only now that I’m starting to accept/embrace it and look for tools that are going to help me live in a predominantly neurotypical world. So money management is one of my first targets, to try and get a grip on my impulsive spending and put some controls in place to help stop myself from spending £12k in 4 months on credit cards again! 
I use YNAB but whilst it helps me see a clearer picture of my finances, I tend to find that it doesn’t do much to stop me impulse spending and half the time I will just ignore the budget. So I’m thinking if I can create something similar at an account level, in the form of pots etc, then I can add that extra layer of friction that might be enough to stop me from making unnecessary purchases.
I also found it interesting to read the comments re how one UI might work for one person and not another. I too struggle with the home page on the Starling app come to think of it, I don’t know why, but there’s something about it that seems to add an extra step for my brain to process what to do next. First Direct’s UI is very clean and simple, which I like, however, the lack of transaction detail (e.g. whether a transaction is a DD, Debit card payment etc) really impacts me and I find it quite difficult to process.
So Monzo definitely sounds like a promising choice and I think I just need to give it a go and see how I get on with the app.
Thanks so much again for all your help. I’ll report back once I’ve opened the Monzo account and given it a whirl.
David 