Our ramp is probably 2" or 3" per/ft, quite steep really. Yours is rather shallow, so I bet you likely will need the tongue extension to get through the sand traps.

My trailer doesn't have a bow stop. I put the trailer under the boat a few times without one, then thought it would be nice to have. So I welded up a stand (with steps!) and affixed it to the trailer with the boat in place. Launched o.k. but then when floating back on I couldn't get the boat close enough nor attached without slack such that when out of the water the boat was actually against the chock. The rope would stretch, or the tower bent under load, I'm not sure which, but once out of the water she was always at least a couple inches away, if not more. I guess this is why the powerboats have winches and rollers, to snug up after hauling... or at least put major tension on.

I removed the bow chock/tower because it was largely ineffective, and if the boat stood off the stand it would be bad for my tongue weight.

I found that sinking the trailer so that the pads hitting just forward of the keel were slightly higher than I want, I can get her to set well as a result of slight forward momentum (takes a bit of getting used to). The biggest problem for me is getting the stern to stay straight as she came out of the water, but I don't have keel guides.

It's even easier if you can be aboard and use your body as movable ballast. If you are in the stern and line her up and in straight, then move forward to the bow, she'll settle down on those pads nicely. Seems silly, but it only takes a fraction of waterline to go from float to not!

I always have a long bow line that is tied to the truck during any movement on an incline. That's my insurance to keep the boat on the trailer, but I've never seen it even slip a little, though the boat in question is lighter than a J/30.