Back on topic. One past consideration was car visibility from the road, not sure if that really matters now or not. The Duluth Diner is just too small, and now too busy.
The R.O.M.E.O. hot rod guys meet at Marietta Diner. Huge parking lot, lots of seating as 50 guys go on Tuesday mornings. Never been inside though can't get their early enough so not sure if they seat as a large group or table by table. Luckys burgers and brew in Marietta was a spot for one of my clubs. They have an outdoor pavilion for nice weather that is dog friendly, indoor seating is possible as they have a bump out area with tables they will reserve for big groups with notice. The old blind dog in Brookhaven has a side room that would fit us all. JR's Log House on 141, we went there once when Galaxy closed. This is where the V8 club meets. Lots of room, will reserve with notice, average food. How about a Marlos Tavern? They advertise that they take groups. Not a huge fan of IHOP, service tends to stink, food blah, and not really set up for large groups bring mostly booths.
If we go regularly anywhere they are more likely to save us a spot. JRs is great that way, we tell them a month ahead and are good to go.
Might also consider a day and time change. 1:30 kills a whole Saturday. With kids and events in non-covid times it is hard to get there. How about 7pm dinner on a Tuesday? Or 7am on Saturday?