How would the three round tables fit with the long ones?
 Did we want a long head table with the wedding party? - would this include the three wives/fiancees of David's groomsmen? Would that make the table lopsided?
 We need to designate an alcohol-free zone for some guests - is this possible with long tables?
 If we are pushing small tables together to make long ones, how many do we need to fit all of our guests?
 Do we want the tables facing the same direction or more in a U-shape?
 etc. etc. etc.
After many rough sketches and ideas, we came up with this:
personal photo created roughly on indesign.
(The long rectangles in the center of the tables are the runners, and the little circles are where the centerpieces will be)
We decided that a long, head table in front with all of our wedding party (15 people when the wives are included) on one side would end up looking kinda goofy - especially when David and I wouldn't even be in the center since there would be three extra people on his side. Plus, a table that long with people only on one side makes conversation pretty awkward. While briefly considering a sweetheart table to avoid the large wedding party awkwardness, we decided that using the round tables up front and seating us with just our siblings would work just fine. Then, the other two round tables could seat the rest of our wedding party and our most important family members.
I like this setting better than a head table where we're clearly at the front of the room, center of attention. We will still be in front and be able to look out over all of our guests, but it helps us also be in the middle of the action instead of being so set apart.
We figured if each 5' round table seated approximately 8 people (though I think they technically fit 10), we could have three 15' rectangle tables that could fit 18-20 people each. David did some crazy math with the round tables' circumference and the other tables' areas to figure out that one... I just went along with it. Voila! We have enough seats in the house.
The only remaining sticky spot was leaving an alcohol-free zone. If we had small individual tables, we could designate a specific table where we could tell the staff to not serve any wine - problem solved. But, we couldn't expect all 20-ish people at a long table to not be drinking. We have solved this problem by seating the folks who really struggle with alcohol on the very end (by the cakes to distract them ;) ), surrounding them by other people who we know will not be drinking, and calling that end of the table alcohol-free. We can create an invisible barrier between the person who is least offended by alcohol but still won't be drinking and the rest of the table and instruct the staff accordingly.
Now, we also did some crazy measurements (David whipped out some fancy math again - this time I helped) and decided that in order for all of this to fit, the room has to be at least 33 feet wide and 30 feet long (longer if we're fitting the cake and gifts tables). Now, here's the thing... I don't actually have any idea how big the room is. I e-mailed the lodge asking if the three round tables would fit in front side by side and explained that we wanted long tables running out from there, and I'm just crossing my fingers in hopes that this is possible. I figure next time we communicate, I will tell them our measurements, ask about the exact measurements of the room, and maybe show them our picture. Gosh, I hope it works - starting all over again could get complicated!