How wonderful that someone's thinking about and practicing a recovery -- and is honest and caring enough to report problems! That's step 1 in addressing an issue that most people prefer to wish away.
Here are two suggestions based on lots of study, lots of tests, and lots of talking with people who've gone through a real emergency:
1. During practice, a life jacket or cushion in the water will blow with the wind faster than a human body. For a more realistic simulation, attach a drogue (small parachute) or counterweight (maybe a coffee cup will do).
2. For a report on the most thorough tests I know, go to either of these links:
and click on COB Final Report.
I wrote it, but all the work was done by the testers during four days of trials on SF Bay -- 400 tests in monohulls, multihulls, and powerboats from 23-54 feet. There are lots of hard facts and informed opinions on maneuvers (several choices), ladders (they don't always work), boarding platforms (problematic), throwbags (great idea), Lifeslings (another great idea), emergency lights (many recent improvements), and COB alarm systems (improving).
The report's in the public domain. Anybody can use or distribute it in any way so long as it's constructive. Any questions? Let me know.