The aquarium in my photo in my account is peninsula. Even if there are just frags and 1 clownfish, it makes a comforting room divider that creates a distinct work area from the bigger room. The one challenge is flow; I addressed this using Neptune powerheads. In wave mode, compared to a normal tank, this presents a very compelling and dramatic display.
I've had both, and I definitely love this peninsula setup the best. I can enjoy the reef tank, the people on Meet / Zoom / Twitch can enjoy the reef tank, someone sitting on sofa on other side can enjoy the reef tank ...
.. even walking by you can enjoy it too. Ryan from BRSTV mentioned he uses the exact same sort of setup (peninsula to partition off an area for work).
This brings me to second challenge (which is a nice challenge): because the display can be viewed from at least 2 or maybe even 3 sides, the aquascaping/habitat and coral placement would need to reflect that. This affords a bit of extra space for corals, because on a non-peninsula tank, one wouldn't place corals in the back behind rock-work where nobody can see them. I view this as an advantage, because you can have more corals, and you can have areas with different kinds of corals.
I would point out too that the tip of the peninsula will have lowest flow, and nuisance algae has a better chance to take hold there. However, one can also use that space to grow low flow corals that otherwise would need special considerations if your SPS tank is a ultra high flow setup.
Remember to consider the height of the aquarium from at least 2 sides, not just from 1 side (e.g., in my case, while in front of computers I would be sitting, but my chair isn't the safe height as sofa. Obviously, I picked "walking/standing" deprioritised.
