I’m in a similar situation although my kids 7 months old. I got s smart trainer. Messed around with rouvey for a bit but now I just do training plan stuff on training peaks before the fsmily get up.
I had a dumb trainer in the past and never used it.
My point is I would strongly advise a smart trainer even if you have to go second hand.
Use flats or clips. I’d put the cx bike on. With limited time you want everything ready to go straight away.
If you stick with it you’ll get much much fitter.