There are 2 things about Sarius's prescription that don't make sense to me, even aside from opinions on the quality of the show itself.
1) That stronger ongoing story arcs will bring in a wider audience. Not "stronger" as in "better", because obviously better is better, but as in more continuously serialized. The big network hits, the Two and a Halfs and BBTs, are not known for having strong seasonal arcs. I'd say The Office is probably the most serialized a sitcom has been while being a real breakout hit, and it's the exception that proves the rule.
2) Even given that the parody episodes are alienating some of a wider audience, they're also what attracted the loyal fanbase the show does have. Ditching those to go in a more CBS-y direction may or may not succeed in bringing in a wider audience, but it will certainly come at a cost to the rabid core and critical acclaim that the show can rely on now. Going safer and broader is something many shows do, but when they aren't working. Community is working, albeit not as well as anyone would really like. Sacrificing what the show does have going for it in the mere hope that its not too late to rebrand it as something less challenging strikes me as a bad bet. It's guaranteed downside in exchange for a nebulous upside that may not materialize at all, even leaving aside how transparent and craven it would be artistically.