I think that party size to drop rate is an EXCELLENT idea it wont matter if you wish to solo, 4 man team or full 8 size team, your drops will be the same that is BALANCE that is what Anet want.
This will help drastically reduce solo chest runners, farmers (underword) etc from becomming more rich then anyone else... balance.... perfect.
it would be like having an invisable henchman for every space that can be filled in your party nicking items, it would be total balance.
you would not need to incease drop rates, keep them as they are now or slightly higher as Anet will know it wont benifit soloers so they wont have to worry about nerfing so much.
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