I hadn't built a PC since about 2010 and spotted the Antec Striker case a couple of times and had to build one. Ended up going waay over budget on this but I'm happy with how it turned out.
I had a few compatibility warnings on here about the GPU being too long for the case, but because it sits vertically at the front of it I just ignored it and figured I'd make it work. It fits just fine. The EK D5 water pump was way bigger than I expected, and would have completely stopped me putting the glass back on the case if I mounted it where I originally planned to, so I ended up drilling mounting holes into one of the inner plates of the Striker case so I could mount the reservoir and the pump back to back on the same plate.
You can't really pick watercooling parts on PCPP, so here's the details - I'm using a 250mm Barrow boxfish reservoir - I looked at a bunch of reservoirs and the measurements of this seemed like it would fit the space nicely. CPU water block is a Phanteks Glacier C350a. Radiator and all of the fittings and the little water filter are all by Bykski. Water pump is an EK-Quantum Inertia D5. I used 14mm acrylic tubing for everything because it looked like it would be the clearest and nicest looking and I like a challenge. 14mm was an arbitrary diameter, I'd happily have used 16 or 12 either. It worked out well though but it is a pain in the ass to cut... The fans are 120mm EK-Vardar X3Ms.
You can't get a water block for this GPU yet, but when you can I'll extend the loop to cool that too. The pump is overkill for the current setup but will work well for when there's another rad and water block. I haven't had a chance to game on this too much yet, but so far it's handled anything I've thrown at it.
Pain points when I was building it: I had two separate deliveries from UPS feel damp when they arrived. Because of covid restrictions they were just dumping packages at the entrance to our building and not waiting for people to come out. The first package had the SSD and the CPU. Box felt a bit damp but I thought maybe it was just from the cold. A few weeks later I had another delivery for the motherboard, fans and pump. This time the outer box was perfect, and when I opened it everything was destroyed with water. It was like they'd been sitting in the rain for a few days and then when UPS saw how bad it was they put the contents into a fresh box and just delivered it. I've attached pics of how bad it was. Luckily the motherboard was in a static bag inside the box and works fine - but I was extremely pissed at the time. Still am. Will never use UPS again after it.