Congratulations for coming back to ponies! :-D Once the current lockdown has passed, I would recommend seeing if you could do lessons a bit more frequently (at least once a week). A "working" loan or share at a riding school sounds like a really good first step into sharing, and a good way to become familiar with how it works and what is required.
I came back to riding after a break for PG uni stuff, and I started with lessons at a riding school-3/week for a short period-and after a year, I suddenly had a pony of my own. But I had lots of support, and was only 10min hacking away from the riding school. That was really important! I think the point when people get into trouble is when they try to go it alone without being able to get professional support. And it's important to be competent enough to know when you need to ask for help, if that makes sense.
I now have a sharer for one of my ponies (somehow, I've now got 2 ponies and a horse; not quite sure how that happened...) who also came back to riding as an adult. Her situation is more like yours, in that she rode a bit less than I did as a child, and re-started a bit later as an adult. She started up again by joining group lessons and hacks at a riding school. Then, she shared a very safe pony that she knew from the riding school, and now, she is hacking and schooling my young pony, but with lots of help. It's a good situation for everyone!
For your current ambitions, your plan of lessons, and then eventually a share at the riding school, and perhaps after that a share elsewhere, sounds like a very reasonable plan.
I would say, go for it! 30min drive is really nothing much, twice a week. Think of how long it takes people to take a bus to work.