It appears there will be 3 different models (Base, NEXT Advance & NEXT Pro) of the AYANEO NEXT, and will all be viable alternatives for people who don't get a Steam Deck, although these are drastically more expensive. The base model runs $1265 on Indiegogo pre-order and increases to $1315 retail. The "Pro" model is $1465 on pre-order with a retail price of $1565. Personally, I'm sticking with the more capable Steam Deck at these prices.
Judging by the specs below, these should be able to handle most handheld PC gaming desires but at a very high cost (price well above value I think)...