I would avoid games workshop hq at this time of year tbh. It will be full of screaming children running about with no regard for others. I've nearly been knocked down on the stairs (I'm 23 and in fair health before you presume that I may be old, slow or in bad shape), I've nearly hit kids before realising they were kids as they jump out from behind statues screaming at people at the top of stairs trying to scare them. It's a miracle there haven't been any serious injuries.
I love the hobby and only live a 10 min walk from their hq, but I generally tend of avoid it, especially when kids are out of school as a lot of parents treat it (bearing in mind, at it's very core it is a retail store, museum and bar) as a day care centre. Drop them off in the morning, pick them up at closing time. For me, it's now generally a case of go in, buy what I want, get out.
Back to other photographic ideas;
There is a ruined church called saint Mary's in colston Bassett, just outside of Nottingham that is absolutely gorgeous (10 - 20 min drive from city centre). You should be able to google a post code.
Wollaton hall and park, where they filmed some scenes in the latest batman movie (it's the new Wayne manor), and there's deer roaming about in the park.
If you want wildlife, predominantly birds there's the Attenborough nature reserve about 4 miles from the city centre just past beeston. Quite nice to walk around, it also has a handful of hides for you to watch and photograph wildlife from.