alright i did some math... feel free to double check it... cbr, riviera, pop and aoa total to about 7000 rooms (many are suites so u can probably average total occupancy to about 3-4 ppl per room which cld be 21000-30000 more people at the IG
the current ig resorts are just shy of 4000 rooms (yacht, beach, boardwalk, and swan and dolphin)
can IG accomodate close to 3x the guests that it does currently? anyone else have thoughts?
I think your math is a bit off.
Yacht: 630
Beach Club Hotel: 583
Beach Club Villas: 208
Boardwalk Inn: 378
BoardWalk Villas: 383
Swan: 758
Dolphin: 1509
Total: 4449
Taking into account estimates for the number of rooms lost at CBR and how many will be added at Riviera, I'm coming up with about 6600 at AOA + POP + CBR + RIV combined.
Then when we start to factor room occupancy, things get tricky. Most of the Deluxe rooms in the BW area can sleep 5 guests. That includes rooms at Yacht, Beach, Boardwalk and Dolphin. The DVC Villa numbers are expressed in terms of 2 bedroom equivalencies, so that's around 600 rooms which allow up to 9 guests.
On the other side, the AOA suites are capped at 6. The AOA hotel rooms and POP (3800 of the 6600 rooms) are capped at 4. We can only make estimates for Riviera. Disney has said it would have about 300 rooms, but no details on the makeup of those rooms. DVC resorts are often all 2B equivalents, but at Riviera there have been rumors of an unusually high number of studio rooms (4-5 occupants) in that count.
Add it all up and I'd estimate about a 125% increase in traffic. And that assumes guests from the Skyliner resorts visit Epcot as often as guests at Beach/Yacht/BW/Dolphin/Swan. Maybe people staying in the Epcot area already spend a disproportionately high amount of their time at Epcot.
Regardless, figure the IG traffic will a little more than double. But it's also arriving at a slow and steady pace rather than overwhelming masses one normally sees at a theme park gate when a monorail/tram/bus/boat arrives and deposits literally hundreds of guests at once.
There will be more guest traffic in the International Gateway area, but personally I don't think the entry gates will often be overwhelmed. Things may get backed up at times, but I don't think we'll often see lines 40 people deep like a main entrance.
Leaving the park after fireworks will be a different story, but it won't impact guests staying at the Epcot resorts who are leaving on foot.