I've worked wood since the 70's and it has been both My father and my sole source of heat since then. We have 180 cord under roof right now and that's about an 8 year supply for us. we just enjoy doing it together.
I've used a lot of different splitters and it all boils down to what you want. There are pluses and minuses with the designs as noted above. We have 2 splitters currently and I'm making my splitter now from everything I've learned/wanted over the years.
I'm getting older and looking towards the future to make it easier. I have a boiler so if I can carry it, I can burn it. Dad likes them smaller so everything gets split to reasonable size.
If your running production with a conveyer then a fixed wedge with adjustable, 4 or 6 way is the way to go. Push it out the end and plie it. Fixed wedge are great for people Bring the wood to the splitter or buy log loads. Again, personal preference applys here as I can't do horizontal. I'm 6'6" and the leaning over or sitting moving stuff around kills me.
With that said, I'm building mine with the wedge on the ram this time. I, Like you, don't like the dragging back and we have a fixed table on one of ours. I'm going with swing away tables on both sides so you have the option. Boom crane on the end with cordless remote winch with log tong to retrieve/lift the big ones off the end and swing around to the splitter. I'm putting stabilizers with cylinders(think backhoe type) on the end . My beam will be 40" high as that is my comfort zone on leaning. I put our old splitter up that high and it was astounding the difference on how I felt at the end of the day. Roll off's and such weren't a problem.
When we cut big trees we back the splitter down the log length and throw the wood to the sides. then when it all split we back the trucks in and load from both sides. This method just works the best for us. I don't skid logs.
I've dealing with a guy who has built splitters and knows his stuff:
LOG SPLITTER | WOOD SPLITTERS | HYDRAULIC CYLINDERS
He's supplied some parts and I'm doing the build. I'm using a 6" X 8" box beam that is 1/2" thick. They use this as well and weld a 2" thick mill plate on top of that for a slider. When Mounting the wedge on the ram he said no more than 8 inches high as it will put too much strain if higher. Two stage wedge as others have said will help with the sticking but the stops are needed in case. Another secret is to have the backstop big enough that the wood doesn't "curl" around it. If it Holds the corners the wood actually moves TOWARDS the wedge and busts quicker. Hard to explain but think about how it would split with a wall behind it.
Check out Tempest splitters on Utube. They have a pretty neat design as well and send wood out both sides. Too small for me as they make a lot of slivers but interesting .