A lot of things could effect braking. Could have had fork seals leak at one time and contaminated the pads.
I'd flush the brake system and put new fluid in, and change out the pads. That will give you a good baseline to begin with. Yes you could put new lines on but if they are not cracked, I'd say leave them. I'm running stock lines on my old K's yet, no problems.
As for warmup, I'd say you might do well to do a good carb clean up. It's always good to baseline all aspects of your bike, carb clean and sync, oil chainges (fork and engine), set valves, lube swingarm bearings. I'd also recommend getting an oil pan gasket and drop the pan to clean it out and check the health of the motor. That can tell you a LOT.
Resist the urge to go electronic ignition etc. Mark your points plate, pull it, pull the advancer and lube it up good, that is very important. The put your points back in per the marks you made, give them a light clean up with emery cloth, and set your points per the manual. Make sure you lube the points heal ligtly with some grease and ride on. Those old points will last you a good long time if you take care of everything.
As for that burnt oil smell, it's likely your engine blow by tube. There is a tube that runs from the top of the motor on the cam cover down towards the rear wheel. Especially since you let it sit and idle, you are likely smelling those fumes, plus any unburned fumes from the idling.
If the bike has spent a lot of time sitting, you could also have some sticking rings. Would do well to run a compression check just to see how things are. If you have some low cylinders, that could contribute to blow by and thus the smell. A good dose of marvel mystery oil in the cylinders over a period of many days, repeating, then drain the oil. That could possibly loosen up stuck rings.
These motors are almost indestructable with just a reasonable amount of care, but the best thing you can do is baseline the mechanicals first then keep up on maintenance.
