Thanks for your help. I've been thinking that a magnolia might be nice and Daleys have a gorgeous one in production at the moment so I might just rein in my impatience and get one when they're ready. They have a dwarf mulberry and chinese pistachio too so I can order them all in one hit and keep down delivery costs.
I just got 2 Japanese Maple on ebay for 99c (bargain!!!) but I think I'll just keep them in pots on the patio instead of planting them.
I love silver birch and there's a spot in the back-yard that I think they might work so I might just pop them out there instead of the front yard.

So I'm still on the hunt for another one or 2 species for the front lol.