I am curious if say you could be at a slight zoom, but doing so causes you to have to stop down with it, is it a possible better idea to use a good 2x or 1.4 tele adapter and stay at the wider aperature?

Would you lose a lot of light? Would you gain shallower depth of field?

You will have to check optical details on the adapter you are considering. Many are partial zoom and will vignette if you go too wide, and some may cost you a stop or two. There is no hard, fast rule. Depth of field with/without the adapter should be the same for the same effective focal length.

And it may be heavy, the Century 1.6x for the A1 weighs in at about 25 oz, or 1/3 the weight of the A1.