Personally, I would pick Marina Suite at this time

• The main building is a large tower and I envision potential elevator sharing issues (not based on this hotel in particular - but other hotels I have stayed at during this period)
• On the other hand, the Marina building is low rise and the actual rooms are exterior entry, so there is much less opportunity to be crowded in hallways/etc. with random people
• I last stayed here in February and was upgraded to a Marina Suite, I have a short review upthread. In short, the room looked like it had been refreshed fairly recently.

So I haven't stayed here during COVID but simply due to elevator/crowding logistics, I would pick the Marina building to avoid any crowding issues in the main tower. My family of 3 has traveled a fair bit this summer and we find the greatest source of COVID anxiety is lobby/elevator crowding, this can mostly be avoided in the Marina bldg.

Additionally, those Corner suites are not proper suites, they're just big rooms. When I went in February, I was with a friend and it was invaluable to have the proper suite in the Marina building so I could work while he was asleep. So if working is a consideration, again I would consider Marina Suite.