Regarding travel into Bristol, just to clarify it is likely only one of us will be doing this with any regularity. Train would almost certainly be the preferred method, so as long as there was a station available, and the train went into Temple Meads, that would be one problem partly sorted. Obviously the shorter the train journey, the better. Part of our current predicament is that child care will likely not be compatible with a 1 hr 40 commute into London for my other half. Unfortunately my work does not mean I can always plan to assist with a child care pick up/ drop off, as I am often leaving/arriving too early/late, or staying away.
I would likely be heading further afield, likely on the M4.
I have heard traffic is an absolute nightmare round Bristol, so was thinking it would be best to only attempt commuting by car if you we're going against the flow, I.e. away from Bristol. Trains unfortunately would be rammed, but my wife has commuted ( as have I ) into London for a few years and after a while you just accept the trains will be packed if you get one much after 7am.