The 3-in-1 sets (where the set numbers actually begin with 31) should really be the first thing you look at when choosing a set for a child, and they deserve more praise. There are a lot of cool 3-in-1 sets out there. That castle (31168) is really good (and those horses are too!), and the haunted mansion (31167) is just cool with minifigs which are a hit with any kid.

For a small and cheap present that hamster (31376) is just too cute to pass up too.

It feels like those sets are where the Lego designers get to do their thing and do it right, without the weight of licenced IP (of which there is so much) and the trite offerings of the City range.