Apple Core, help a guy out.

Okay.

So - I'm looking to replace my 5 year old Nokia E71 (had it since I was 14) with an iPhone 5S, I thought I might as well since the UI is finally at a place I want it to be (yeah, I played the waiting game for that long). Anyway, I also plan on getting an iPad Mini this year, the new one, so now it's just a matter of which models I purchase.

At first I was thinking of getting an iPhone 5S 16GB, on contract, but the 32GB is only £5 more a month... so can anyone tell me wether or not I should go for the larger memory? I currently have 8GB worth of music (I curate my collection a lot) but I imagine space get's real tight on an iPhone when you take into account photos/apps etc.

Can anyone give me advice on this? Anyone out there with a iPhone/iPad Mini combo? How is that going for you?

Also, Space Grey or Black? And should I get a 3G iPad Mini?

All advice is appreciated! Thanks!