Tillers have more "feel," are faster to control, can be controlled from a multitude of positions in the cockpit, especially with a tiller extender, sometimes have more "throw" for the rudder angle, don't require an emergency steering wheel if it breaks

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Wheels can take less room in the cockpit, can give you more leverage depending on the design, can require less pressure depending on sailboat balance, are less awkward when there are lots of passengers in the cockpit, are less awkward when needing to handle lines in the cockpit, are steered like a car, so there is no reverse controlling needed like with tillers, the centrally mounted pedestal guard (I see your wheel is transom mount) can give you a nice place to hang things, mount instruments, or mount a cockpit table.
I am sure others will come up with many other great thoughts!