I'm not voting in this project, but I'll throw my two cents in.
I helped compile the aggregate list, and when I saw the number of goalies who appeared on most lists I thought there was the potential to go beyond 40 names.
Of course you may prefer to stop at 40. Thinking back to the defencemen project, I didn't really want to push the defencemen project beyond 60 names because
1. We were at the point of ranking and discussing players who weren't necessarily "greats" but "very-goods", if you will. This meant it was getting harder to rank players and it was probably getting less interesting than the earlier rounds for some participants (although maybe not for the hard-core ATD/MLD junkies

)
2. Sometimes it's better to err on the side of ending too early rather than too late, so it doesn't fizzle out.
On the other hand, you do have a perfectly good aggregate list and project structure that you might want to get the most use out of. THN did something similar in 1997 when they took their list of Top 50 players (compiled from Top 50 lists submitted by voters) and expanded it to a Top 100.