The Rams have had 5 winning seasons in a row and won a Super Bowl last year using this template.
They don't need a wholesale change in draft/development philosophy, imo.
If you add a player who *can* develop into a starter every year, you're doing just fine.
Last year, they got Jackson.
This year they got Bruss.. and we'll see if Arcuri can be something.
Two years ago, they got Anchrum.. who, again.. looked really good in preseason at guard. Solid.
Three years ago they brought in David Edwards.. and Bobby Evans. (I'm merely pointing out the assets-committed thing with Evans)..
Four years ago, they brought in Brian Allen, Joe Noteboom and Jamil Demby (With Demby, I'm again just pointing out resources)
None of this is a "lack of investment."
9 players added in 4 years.. and, yes, I'm counting a UDFA because they were successful in identifying and developing a player. That impacted their draft *this* season.