That's a difficult one - the trouble is that the size of the tent dictates how high it can be!
You might want to have a look at a Khyam Freelander, I'm not sure how small they pack down to, though. Khyam tents
Happy searching
No idea what lightweight really is, would 10kg be too heavy? I'm thinking of the Vango Kairos, gives the head height at least.
Mairi
------------- April/May - Georgia destroyed in high winds sob
May - Loch Ken, 1st outing for the wolf lake
July - Waterside House, Lake District
July - Inside Park, Dorset