When I transitioned from the 727 to the 737 I truly missed the FE. I started as an FE, then FO and finally Capt., so I know how valuable the FE is from several perspectives...
On my 1st airline, all FE's were also pilots and SOP for the approach briefing including showing the approach plate to the F/E...On one or two occasions I actually caught a mistake in the making by the guys up front, as I myself have been saved by my own FE...
In the 727, if there was a commotion in the cabin, or in cargo ops a strange noise or thump or bang coming from the back it was very reassuring to turn around and ask the FE to "Go back there and see what's going on".
Can't do that on a 2 crew A/C...
Paramedics are not the answer as I don't think there has ever been a catastrophic event in aviation due to a "seriously ill" or incapiciated pax...