You need to figure out if you just want to be an individual consultant or hire other staff. If you're looking to build out a business with employees it will be much more challenging as you will need to be a full time sales person, always making sure you have enough work in the pipeline to make sure they get paid, rule 1 is that staff always get paid before you.
I would suggest you find like minded individuals and partner up with them, that way when one of you has a bad week or you need a holiday the other/others can pick up the slack.
Seeing as you have so much experience you should be able to lean on previous employers / colleagues to get contracts, this is how we started out. Once you have a few projects under your belt and a decent website you will need to see if you're getting enough work by word of mouth from previous projects or if you need to invest in marketing. If you stay as a small team it will be much easier to do well via word of mouth if your quality of work is good. At the end of the day it's all about your network and driving quality projects into your business.
I would strongly discourage you from only bringing projects to the POC/MVP state. This is what we did initially but you need a far higher throughput of projects and you're in danger of leaving clients high and dry if they want the idea built out further.
That's how we got started anyway, best of luck with your venture!