Update: we set up the Barney cage last night and Alan LOVES it! I intended to let him explore then move him properly after a couple of nights but he took to it straight away. He sacked off his usual bed and has picked a new one even though we left the old one in.
We've set up a few adventure places which he was cockahoop about. He was playing for hours and seemed very happy. We were unsure about the size at first as the cage looked HUGE but once everything was in it was clear it was so much more suitable. His old cage looks so tiny now :'(
Also i put a sandbath in and he's using it as a toilet! Go on Alan! He was loving having a little wash in there
too so I've set up another one. All tips have smashed it so thank you for your help everyone.
I've attempted to put some photos in i hope this works!