The best whole house air-source heat pumps had a SEER2 of 18.5, or a COP of just under 5.0. I need a COP of over 5 to just break even in terms of cost efficiency. So a heat pump would actually cost me more on an ongoing basis. And the price for a heat pump installation was $10k more than a furnace/AC.
I just couldn't do it. To pay more up front and then ongoing was just too much. If you showed me even a super long range projection of saving money, I would have been down for it, but it just was not there.
If I can get solar on my house it may make sense, I will cross that bridge in a few years as my roof is almost end of life, but that has its own headaches as I have limited space (brownstone, flat roof), and am in a historic district.
Next go around, as heat pump tech improves and hopefully gets cheaper, it will probably make sense, but for me right now, it just didn't work.
OTOH if you’re heating with propane or fuel oil, heat pumps are probably a good alternative.