The 5 game minimum to participate in playoffs was introduced to avoid teams bringing in a "ringer" to gain advantage in the playoffs who does not participate in the league. I played several teams in best of the rest playoffs over the past few years who had difficulties fielding a team with 6 players who fulfilled the 5 game minimum. I would therefore suggest to keep it that way.
The banquet is financed through the team dues, there are no instructions on how the dues are collected within the teams. Although unlikely, it is possible that a player contributes to the dues and then plays (or can play) only once or twice during the season. We should encourage as many members of the league as possible to participate in the banquet, which fosters team spirit and sportsmanship. Also, it allows to transfer information and messages to more members than any other event in the league.

How many people do we normally have at the banquet? Around 150 maybe, give or take a few, including 20-30 paying guests.
I'm sure the executive committee welcomes any proposals for alternative venues for 100+ people. Or are you suggesting to downsize the banquet so we can fit into one of our bars?