When DS was two and a half we got him into pre school for three half days a week, gradually increasing to four half days - I'd have done five but the waiting list was ridiculous! He had a great time there, never had a tantrum or cry because he didn't want to go and have never had tears since he started school either. But, he didn't have the kind of coverage your DH is hoping for OP. Yes, he had a key worker, she had four other kids to work with, keep an eye on etc. As did the other key workers. None of them would be sitting around with time to spare though they'd each have an area to taken charge of - so one would cover the plasticine table, one would do the outside area etc.
Before that he was at home with me. We moved to this area when DS was six months old. I went to two toddler groups a week. One thing I did do, and maybe I was lucky, but I invited other mums to our house for play dates. In the end a small group of us did an informal rota of one mum's house a week. Took the isolation away and meant only one of us had the pain of tidying up!
I used the TV as a babysitter in the mornings whilst I got myself ready. No problem as far as I was concerned. If I got to the 'I need a bit of a break from playing trains yet again' I'd make a cuppa, grab the paper and 'watch' TV with DS for half an hour. Sometimes, when I made a cuppa, I'd let DS tear a teabag up to smell and feel the tea - when we got fancy tea as a gift at Christmas one year we compared that (how 'dusty'is the stuff in teabags compared to the real thing!). Even now, aged six, he loves to help with making drinks so he can smell coffee granules etc.
If I had the patience and was cooking something like cottage pie I'd give him a small piece of cooled boiled potato to squish up, or dried pasta to make into a shaker in a cup if I did a pasta dish and the 'fun'you can have with a sieve and a bit of flour whilst helping mum make a cake or pastry is unbelievable. In fact, DS enjoyed that so much that I would, at least once a week, put a load of newspaper on the kitchen floor, big plastic mat on top, a tray of flour, sieve and toy trucks. Makes a snow mountain. Mum sits in the corner with a book, the radio and has a bit of a break. Vacuum cleaner earns its place in the home and DS has more fun washing his toy cars in bubbly water later.
The point is , if you decide on the SAH route, build in some down time for yourself. The pre school owner said to me she could tell the kids who had been given space (not ignored, but the adult had taken a backseat in play sometimes). They could play alone well, as well as be happy to share and they didn't need to be shown how to use a toy because they'd learned how to explore how things worked. The TV isn't needed for that. DS's favourite 'toy' was a load of margarine tubs, loo roll tubes and all the cushions off the sofa. He made buses, cities, garages, beds for his 'babies' and all I did was threw them on the floor and said 'all yours'.
Final thing, as usual I've gabbled on, have you got a Sure start in your area? As they are run by permanent staff who don't have their own kids with them, unlike some mums and tots groups, they will often be able to help you integrate in a group. Plus they often have offshoots - our local one does bug hunts in the summer and Christmas biscuits or decorations at Christmas. They can also help you find other help (well, my local one can - they helped a friend find her way through the maze to get speech therapy help for her DS) and many have a toy library. They also have staff who can help with ideas. I learned about water and cornflour gloop from a session at my local sure start. I had more fun with that than my son, who must looked at me as if I was potty!
At the end of the day your family will work with whatever decision you make. None of us can go back in time and measure if our kids would have been different if they'd gone to nursery/childminder/SAH so do what you think will be best for you and yours.