I have also tried those Debenhams Maine pull ons. They were really lovely quality, but sadly just too small for me. I'm sure they'd look great for your size, and I'd recommend them.
I had M&S pull on jeans and corduroy trousers, they fitted well and were comfortable. Cotton traders I found a bit short between the crotch and the waist, I have a more shapely derrière (big bum), if I crouched down they would slip down to reveal a ‘builders bum’ . I’m a size 12. 5’ 4”.
I've found, after trying quite a few types of jeans that the best for me is if I buy "proper" jeans but that have added stretch in the material. I too suffer from dodgy thumb joints so this let's me just pull the jeans up as you would leggings/jeggings etc. Best pairs so far have been from Next and Kaleidoscope, various colours and leg styles so lots to choose from.
For every day I have some Cotton traders pull-on jeans. I am your height and size and find the £30 Premium ones very comfortable. These are real stretch denim and are quite thick. They come slightly big if anything, I wear 14 in these but 16 in some other brands. Good luck with your search. www.cottontraders.com/search/?q=pull%20on%20jeans
I like Asda denim jeggings. On me they don't fall down, and wash well and keep their shape. I think it depends partly on your own shape, if they stay up well. I am curvy. For your size I think they'd look great on you. They are a proper thickish denim material.
I have also tried Cotton Traders pull on jeans but these looked baggier, and did keep slipping down, and the material was thinner, not proper denim, which I prefer. Not very flattering.
I am needing a new pair of straight leg jeans. I am finding it increasingly difficult to fasten the button at the waist due to arthritis in my thumb joints. Does anyone wear pull on jeans, do they stay put, or slip down? Which brands would you recommend? I'm a size 14 and 5' 3" in height . Thank you.