I too used to have issues with the Boat Buddy on my 2004 SSV. I replaced it with a roller, but still continued to have issues so I went back to the Boat Buddy. I then figured out what the secret was to getting the boat trailered correctly with the boat buddy.
First off, you cannot have any weight in the bow. If you have ballast full up there you need to empty it first. If you have passengers up there they need to move to the back.
Secondly, the trailer bunks must be thoroughly wet. As mentioned previously, you first must dunk your trailer all the way in the water and then pull it out until about 25-30% of the bunks are out of the water.
Lastly, you need to drive your boat into the trailer with a bit of speed. If you do so the boat will slide all the way up over the boat buddy with no issues.
I live in the Dallas area and in the last 5 years my home lake has been 11 feet low and then 10 feet high. I used all different grades of ramps from steep to shallow. By using the 3 steps I've outlined above I have not had any issues in the last 5 years.
I do agree that modifying your trailer as you have done certainly will make things easier, but if you do not want to go to the trouble or expense the steps I use above will work.