RE: the rooster tail... the official term is visibility spout.. it will help other boats see you coming from about a mile a way and actually for THAT purpose its effective... but IMO its more annoying than helpful, nobody will want to ride 20 feet behind you (not that they would anyway if premixing), if you have to tow somebody the spray will hit them right on top of the head, and if the wind is behind you at idle, you'll occasionally get sprayed with a cold splash which sux....
anyways, if you look down underneath near the pump, you should see the short hose that connects up to the hull, just pop that hose off, and the visibility spout is gone... I actually left mine dangle there, it didn't get in the way of anything, and a couple of times when I was riding offshore I connected it again (no clamp, just shoved it on)
some people get all complicated and put a shut off valve there and such, but just popping it off is the easiest way. Especially if you have long idle's from the ramp to the channel.
1) I'm surprised that it took that long to spray, must have been clogged with debris, normally it sprays even at idle....
2) I'm glad you made it back, (constructive criticism here) but taking the two kids was a bit of a ballsy move for a maiden voyage,,, too many unknowns with that ski at that point...I would have been riding solo and very much preferred to have another ski with me at the time...
The two big concerns would have been
a) it dies on the water and your getting towed (no treat with 3 riders)
b) it sinks and now 3 of you are floating...
But very glad you made it back...