This is all being over-thunk. A 2-speed winch hardly reduces the cranking energy, but it DOES make the job last longer. The OEM winch is not an issue.
It's not rocket science. But it IS an issue with 75% of trailer boaters because the dealers don't know how to teach you, they don't watch other SUCCESSFUL boaters, and they didn't read the "book".
Don't back in so far...
Put EZ Slides on the bunks...
If you want to save money, spray the bunks with PAM before EACH retreival, instead of putting on slides...
If you aren't concerned about money, buy a Powerwinch.