On your first point, the lowland league is less physical than the top divisions - you see that every time a full time team comes to play. Yes the challenges might be a bit heavier, but the physical attributes of the players and the game is lower. That was clear on Wednesday when you saw the build and fitness of the full time Celtic players.
If players are lost to the game it's not because aren't physical enough, that's not the lowland leagues problem, look at Lennon Walker playing for the BU on Wednesday. If you're good enough you'll play.
If playing in competitive environments is important is it not better on loan where games actually matter? Ultimately Rangers B might run away with the league by double digit points but it means nothing. Same if they were in a relegation battle - they're not fighting for the future of the club.
We're not in the dark ages, we have performance schools across the country producing technically fantastic athletes - people like yourself are dismissing this system too quickly. There are one or two B teams that have a decent track record of decent development, there's a lot more that fail and are use to park players.
Anyway can't wait for tomorrows match when Rangers B come to Newtown with players bought for hundreds of thousands of pounds, most likely dominate and we're all think it's great because one day they might play for Scotland. Though they probably won't because any players they actually rate are already in the first team by that age (Lowry, King) or on loan (Kennedy / Mayo / McPake).