Hate to say this, but you guys need a better ventilation system.
Old stove hood above the lead pot. Fan replaced with a surplus nine inch centrifugal blower vented outside like a clothes dryer (metal pipe).
Slightly noisy, but no smoke. Anything that stinks goes under the hood.
Chuck

This is my set-up, in the roof of the garage. large extractor fan with a fabricated steel hood.
Fred

If the flux is a problem there are all manner of fluxes available, one of them will surely do for you.  With regards to lead poisoning, the thing to worry about is the dros, the stuff you flux off and what sticks to your pot.  That stuff is dangerous and is either an oxide or salt of lead, either of which are easily absorbed by mouth, eye, etc.  I used to hang a window fan from the ceiling pointed out the garage door.  When I fluxed w/sawdust it looked like my house was afire, but I never had any lead issues - had it checked regularly until I realized what I did was working.  Primers and residue are poison in the same way.  I always put some mineral spirits in my tumbler to keep the dust down.