I think something like this could definitely be successful and I frequently play on your site.
Move the 1.5k $10 rebuy/addon from 6:30pm to 6pm, keep registration open for two hours (similar to the nightly 10k and 5k). Increase the prizepool to $3k. (I honestly think $4k is plausible in this timeslot)
Work with 888 (shared liquidity) to have the 2.5k $100 High Roller at 7:20pm moved back to an 8pm start time, leaving the structure how it is. Increase the prize pool to $4k (it makes this routinely, and you guys could easily have 80 people in this tournament every night, you get better turnouts on sunday than party/borgata does in their nightly $100 10k)
Continue to have the 10k and the 5k in their given time slots. This gives people a solid lineup. Alot of people have been asking for the 5k to be moved up, but it is successful in its timeslot.. I think a similar tournament alittle earlier could easily get a following, people are definitely on the site as evidence by the entries in the nightly 10k.
So ultimately your 4 big tournaments of the night would be
6pm $3000 $10r/a
7pm $10000 $30r/a
8pm $4000 $100fo
9pm $5000 $10r/a
I don't know, give it a shot, if it doesn't work out you can always just go back to how it is now.