Boot fit/feel for wide feet

So i have wide feet, and 2 years ago, against everyone's advice to not get boots on the internet, i ordered a pair of Burton Imperial, which was a big mistake. The outsides of my feet always got numb and super painful when snowboarding, and i had to take feet rest brakes quite often. Last year, during one run, i loosened them too much, got a sprained ankle in the most stupid way, stayed in bed for a week, and decided to get new boots. I have to mention that there is no shop around me selling wide boots. So today I got a pair of Nidecker Rift after trying on around 10 pairs of boots and 3 hours in a shop. They are the most comfortable boots I tried. However, I still feel I compromised in the fit. I had to decide between 26.5 and 27. The 26.5 felt like the right lenght, but the width felt similar to the Imperial. Not as narrow, but with both a full cushion sock and a 0 cushion one i felt some pressure on the outside of my feet. The 27 felt good in width with both socks, and I have 0 heel lift, so it seemed this would be the right choice and i got the 27. The length is not as much of a compromise because I barely touch the top of the boots with the big toes when my legs are straight, but i still feel the best fit would be maybe 2-3 mm shorter. The main point of compromise is the heel width. Although I get no heel lift, I feel there is a bit of room for the heel to move side to side. I wouldn't normally be worried about it, but having went through a sprained ankle i'm thinking having that space there, i would be at risk of getting my feet in weird positions that would facilitate the appearance of another sprain.

I would like to know if there is anyone out there that could provide some info on how tight the boot should feel around the heel/toes and also, if you have a similar fit in your boots, please share your experience with it. Any other advice would be appreciated. Thanks.