Few points, regards cooking in a tent - those warnings are for noobs.
Nowt wrong with cooking in your porch with
a proper camping stove. Just keep it away from the edges and
take care. As to carbon monoxide, lol, aside from the argument about proper combustion, its a tent, not a hermetically sealed room.
As to tents, think youve got the jist, these days 6kg would get you a full geodesic base camp tent for Everest!
I've personally got an hilleberg atko for backpacking and cycling light (great bit of kit, very easy to erect but bit flappy in high winds), then a vango spirit 200+ (large porch) if with gf - bags of space for 1 person, or two if you get on well and arn't spending all day in there.
Mate has a lightwave trek t0, same function as atko, bit more fiddly to put up, inner first pitch, but solid as a rock in wind and cheaper than an atko.
Here is a thread elsewhere that might help:
http://www.outdoorsmagic.com/forum/forummessages/mps/UTN/19195/dt/4/URN/5/srchdte/0/cp/2/v/8/sp/
Don't spend to long deciding - it can become an obsession
