I did something very similar about a decade ago.
Our 3rd XI had folded 2 seasons beforehand but after an average season in the 2s I felt something needed to be done. I once rather unkindly was told that I only played 2s because my wife had been the scorer, bit harsh for a 20 wickets a season seamer who could bat! However you get the idea about life in our 2s at the time. The other attraction for me was playing with some of the guys I grew up with. I was forcing a few out of retirement to help the colts develop. It felt a good thing to do and I loved most of my 3 years in charge. I was 32 when I took it on so you might have more to offer the higher levels. However, I scored 800 runs and took 40 wickets in my first season as skipper. It felt like my game had improved because I was getting more involved after years of playing bit part roles. That's not to say others weren't getting a game but scratch teams often rely on key players to start with. In future years many of the colts scored maiden tons and 5 wicket hauls, one is now playing first class cricket. This does all rely on goodwill and those players who are regulars in the 3s being keen to nominate you. I think those players you are closest to from that team, you should approach first to sound them out. You might find it difficult to settle in the position with established players around you and for that reason you need their support. It can be an admin nightmare but you'll develop as a person and cricketer very quickly.