My last kayak was a Pro-angler 12. On the new Outback, the place is more limited, so I had to think of rigging deeply.
The first thing that I looked was the possibility of using a transducer with a side view.
The middle hull being lower than the lateral hulls, down slightly probe after cutting protection allows to place it in this wise place:

With a fairly simple system (but long to implement) square slider:

one can lower the probe out of the cavity:

This eliminates the need for mounting on side arm (tedious to mount / unmount and always difficult to have a piece outside the kayak)) or paste it into the shell (with the problem of hatching by tough weather ).
The second point was to turn round hatch a more convenient rectangular hatch, but without having to straddle legs outside the kayak. I placed it in the direction of kayak:

I chose white for harmony with the dune color, but also the least sensitive to the sun.
Two collapsible bowls area comfortably store equipment:

The lithium battery fits into the tailgate, well protected:

The "missile launcher" style rod holders are useless to my taste. those molded of origin are too far, and those that are placed on rails or pedestals do not suit me because I do not like the rods upright on the kayak.
So I installed both horizontally rod holders:

This allows the rods tidy along the hull and protect at beach landing. Drive elastic can be used to maintain them.
A tube cut in a plumbing fitting allows placing a rod vertically to achieve a node for example:

The paddles are placed on the back because there either I do not like them on the sides:

Back and forth trolley:


Why two trolleys? Because with a single rope anchor, floating or not, tends to go under the hull.
With this system, I send either the front or the back, directly on the side.
The Humminbird fishfinder Helix 5 is placed near the seat for readability. Below VHF natural place:

To easily load the kayak on the gallery, no need for sophisticated and expensive system. A kart tire stuck in the rudder can lift the kayak without it slipping:

Simple, easy and free!
sorry for my poor english... 