At Matasano --- and this is back to like 2005 --- we just used an online telephony provider that routed calls to our mobile phones. I'd probably still just do that today.

Landline for incoming customer calls. Technically it's a package deal with the cable internet company.

My cell for real business, like my distributors. Mostly we text.

Nothing sucks about it. People call, we answer.

Google Voice for local, VOIP. ms for toll-free text and call in US and Canada. No live calls. Everything goes to voicemail and we call back.

I use https://www.quo.com/ (previously OpenPhone).

(no affiliation besides being a customer)