How tank colour and dimension can change behavior

Hi all,
I would like to share with you a curiosity, just to know your point of view also.

When I got my snake I decided to prepare him a plastic tank 37 x 25 x 12 cm keeping the same sizes of his usual home (he lived in a rack with the previous owner) just to reduce as much as I could the stress during his home changing. Everything gone fine and after a 7 days about adaptment he started to eat very well !
Now the snake seems to grow up very quickly so (after 4 weeks about adaptment) I decided to move him in a bigger tank 60 x 40 x 20 cm, in order to take inside it up to his adult size without changing anymore. I put all his old stuff inside hoping to reduce the stress issue and I just added one hide in the cold zone, same umidity and temperature values. The difference between plastic tanks are dimensions but most of all the colour, the previous one was transparent , the current one is white coloured and it does not allow to see inside/outside. I made air holes and a central bigger hole that allows me to check inside.

I know BPs are very sensitive to big spaces (even if he is going over 60 cm long) and I noticed many differences in the snake behavior:

- The snake lives in a not used (warmed) room , without people or noises.
- In the previous tank he had just one hide (warm side) and he never gone out from it. Now he as got 2 (warm/cold) and they are rarely used.
- In the previous cage I never saw him going into the cold zone, now I often see him staying there and moving to the warm side when he need
- When in the cold zone he assumes the "ball" position but taking the head above his body (not hiding it) so I think he is relaxed
- When in the warm side he usually stays more stretched and relaxed , in both cases outside from his hides.

They seems all positive to me , but I would be glad if you could share similar experiences just to better understand their particular behavior.
After 3 days adaptment I am going to try to feed him today , so I can really realize if he is fine or not.

Biss