Jackdaws just drop sticks down your chimney until some of them stick fast, then they drop more down to build up their nest. A jackdaw-treated chimney can have an awful lot of sticks in it. A cowl with mesh is a must round here. A smoke-tight chimney flue in sound condition doesn't need to be lined. I have one lined with lightweight concrete (insisted on by our ignorant mortgage provider 32 years ago) and one not, both signed off. They've been checked out by a HETAS engineer. They both draw really well. We burn a mix of smokeless fuel (Homefire Ovals) and wood in multifuel stoves. Some of the wood is my own, dried for at least a long summer. The rest is mostly kiln-dried. It costs more but it burns much better than just seasoned. Our chimneys are swept once a year, about now. When you first light a fire it's best to get the flue very hot before shutting down. That way, the flue draws better and you get far less creosote build-up. Those expensive things that you sprinkle on a low fire, supposedly to make your soot come loose, don't work and, if used when the flue is dirty, increase the risk of a blocked flue and/or chimney fires. Save yer money and get your flue hot every time.

Yiu can't just buy a stove and whack it in yourself any more. You must abide by fairly strict building regs which stipulate minimum distances from walls and carpeted floor, and, if your stove is more than 5kw output, there are extra stipulations regarding room ventilation. You're not even allowed to move a stove without aproval by a qualified heating engineer.