I like the single piece non-adjustable rod holders that push in the existing rod holder holes - two for the front. Nothing for the back. Strong and simple is the best for me. All the poles I have fit in these two holders.
I peddle an Outback, so I prefer holding my trolling rod in my hands. If you are paddling and want to troll, you may want something adjustable or at a better angle to get your line closer to the water or out of the way of other things.
When I reach behind me, it's easier to grab my gaff, etc., out of the holes in the kayak rather than from extended rod holders.
I had two different Scotty rod holders and didn't care for them. The way they grip the pole is too limiting and would not fit all my poles as I rotate them into use. One was for a fly rod that fit nothing but some fly rods, and the other was for a baitcaster or small conventional reel. It required strapping my pole in with a rubber strap that was a nuisance and it made me nervous about losing my pole if a big fish hit it, or that I would lose time trying to monkey it out of the holder to catch my fish before I lose it. My bigger poles and reels would not fit.
I bought the new multi-purpose adjustable rod holder from Hobie. Too much fiddle-factor so I sold it.
I added two additional rod holders on my Livewell bait tank, bringing the total to 5. That was a good productivity move. It's the best place to stow things straight up and out of the way. Those holders look like the first picture cut off just below the leash clips.
I like to keep my work space simple and clutter free. Nothing more than what I need.