Don't worry about stuff - you've found your way to what's possibly (probably/definitely!) the best RIB resource around.
As regards difficulty of slipways, it's a matter of trying them, and just having your wits about you. We all make daft mistakes (or is it just me?
) and then like to warn others about them, at which point they escalate in gravity, perhaps through exaggeration (surely not!
) or just because our combination of events was unique.
I used to be a mountaineer, and there was a saying which sort of adapts for other adventure-type sports...
"It's not a sport for beginners"
And it's at that point that you realise that you've just gotta get out and do it and make your own mistakes!
But anyway, there's a thread here about the difficulty of launching called "size versus an easy life"....
My own favorite launching tactic is to keep a very, very long length (30m ish) of cheap (polypropylene) rope in the car so that my motor stays on the dry bit ('cos I ain't gotta four-by-four) and I can wrap it around the tow hitch to "lower" the trailer into the wet stuff.