Cool setup. Wish I could go for something like that. Being said, I'd probably got for the Ultra-wide or Single Large. The Eyefinity setup were good back then but now considering with large and wide, those monitor breaks in-between is a bit odd for me unless its really frame-less, but still there is a line in between. Multiple monitors does come in handy for working purposes like video editing or other software's with loads, and scads of tools. I think for gaming other two options are great and with type of games you're are into, views of vast horizons would look incredibly dashing on a Ultra-wide. So in this instance I say Ultra-wide.
As for the display port, All the monitors you listed except for the ARC comes with both HDMI 2.1 and DP 1.4 and apart from the bandwidth difference, both ports support 4K@120 Hz. So if you are planning to use multiple monitors you can use all ports. But if using a single monitor setup, you probably should go with the HDMI 2.1 having a higher bandwidth. The DisplayPort was superior in bandwidth until HDMI released the upgraded version. Still the Display Ports win compared to the technologies like the Multi-Stream Transport, USB-C Alt-Mode or Variable Refresh Rate etc. HDMI got similarly and can achieve results just in a less convenient way. Also the DisplayPort 2.0 has also been announced years ago, with even higher maximum bandwidth than HDMI 2.1 at nearly triple the bandwidth of DisplayPort 1.4. Be no sign of it being integrated yet. So with the existing choices, it really depends on your setup.
