Rams approach is right in the long run. In the short term:
I would call securing services of OL men like Mathis or anyone equivalent before training camp ends is an absolute bare minimum this teams needs to do to stay relevant in the first 5 games. We haven't yet talked about rehabbing #1 WR and #1 RB with a new QB and a new OC under center.
1. Greg Robinson was very raw and had not done much in the passing game and was very young. Havenstein & Brown had a ton of starts at the collegiate level and the transition should not be as turbulent. I also felt Greg Robinson played very well considering, IMO, it was overstated with his struggles although he does need to be more cognizant of stunts.
2/3. As to depth concerns that is why they drafted four offensive linemen they actually have more depth now then they've ever had including a possible gem in UDRFA LT Darrel Williams. Also you forget about Garrett Reynolds who has had starts at RT and Guard in the past along veterans that could be released on cut down days.
4. Again Robinson was drafted for his ceiling Havenstein & Brown are more game ready based on the fact they were seniors and the both of them played in a pro style attack. Again Havenstein & Brown are game ready.
More importantly let's see what the kids have got before you start yelling fire in the theater. In preseason if they showcase otherwise you can always make a trade for a veteran or again one always seems to shake lose as well.
IMO I'd rather go young and I understand you don't have the stomach for slow start again none of us do, however, I believe in this group much more than to begin the season with a cast of castoffs. We've tried that now just let the kids play!