No. A southern conference would be a 4 th division.
The standards will never rise in the south unless they are tested against the Northern sides.
Travel is an issue but there has been professional sport for well over a hundred years, for a lot of that time there were no motorways. Coventry to Barrow in the 1950's was a six hour trip by train and about 8 hours by car. There was a time when in the old Football League 3rd division North they had to do that journey.
When Coventry played in the old Northern Union before WW1 a trip to the heartlands would have been done on public transport, trains and buses!
Today's players travel in luxury coaches with toilets and kitchens. Coventry's bus has Wifi and Sky TV.
So yes it's a full day and it's not helped that match day is now usually Sunday and not Saturday as it was in days of yore but that's the clubs choice not the leagues.
I agree on your point about standards - but these lads are part time players. To haul Barrow to Mountain Ash or Skolars to Newcastle is harsh. And where do you imagine a Tier 3 club gets its hands on a 'luxury coach'. A chemical toilet and a tea machine don't much make up for having to get up at 5.30 having got in at 1am having taken a physical battering.
If Tier three were to split now like SL/The Championship, yes, all the development clubs would be lumped in together. Perhaps that is the answer...