Windward leeward races are a lot more tactical than 60 degree triangles.
I think a mix is good.
I think up to 4 races a day is also good.
I think that it should be run over at least 4 sailing days.
Maybe schedule a triangle race with a 80 degree reach for the morning race and have 2 windward leeward races in the afternoon.
If you lose some races you could go to 4 a day when the weather is good.
Here is a plan. Measure sunday, invitation monday morning, 2 short races in afternoon. Tuesday: 1 triangle race in morning, 2 short winward returns in afternoon.
Wednesday: 2 short races in morning, 1 triangle race in afternoon. Thursday: rest day with resails provision. Friday: 1 triangle race in morning, 2 short races in afternoon. Saturday: 2 short races in morning, 1 triangle race in afternoon. Saturday night dinner, Sunday: Go home.
14 races. 1 Drop after 6 races, 2 drops after 12
Try hard to get 14 races by running up to 4 on the last couple of days.

Regards
Chris.