It was all very impressive and well done on organising a bjj event like this.
I can see the pros and cons of both points tournaments and submission only events.
The problem with submission only events is that people will go for submissions which lose position like many leglocks. Getting and defended position is just and in some cases more important than submissions.
I believe leglocks should be left to the higher belts especially heel hooks and toe holds. Knee bars and achilles ankle locks are ok at the blue belt stage.
The problem with points tournaments is that you will get people getting a few points then stall for the rest of the match.
Especially people who have a background in wrestling and judo, Jeff Monson is a good example of this. He takes people down, they go to guard and he stalls till the time ran out. Well that was what I was told by people who watched the 10k challenge in the UK.
Im not sure how its possible to find a middle ground. Perhaps point deductions for stalling?