So I’m running with your gradual increase option,
@BGinGA but was wondering how adding a single rebuy and single addon option affects time. How would you calculate that without knowing how many more chips are being added to the pool. I was thinking about a buyin of $60, $2 rebuy for T20k, $20 for T20k addon and if you still have your one rebuy token you could turn it in for an additional T10k. Is that too much in chips?
I think ^that is way too many chips. With 20k starting stacks (which equals 200bb, plenty deep already), you really don't add much value to the structure with a huge 20k add-on
plus a 10k unused re-buy redemption.
I'd structure it as follows:
$60/20k buy-in
$60/20k single re-buy (cooler insurance)
$20/10k add-on (optional)
free/5k add-on for unused re-buy chip
(So all-in for either $140/50k, $120/40k, $80/35k, or $60/25k, and it's pretty balanced at 0.28c/chip, 0.30c/chip, 0.23c/chip, or 0.25c/chip -- meaning that purchasing the add-on is a good value while rebuying is -ev, but all decisions have a relatively minor impact on equity).
The $20/10k add-on adds additional cash to the prize pool (and mostly just helps the shorter stacks survive a little longer after the end of re-buys), while the free 5k add-on gives the re-buy chip some actual value and helps discourages crazy early play.... and neither will significantly skew the value of the chips already in play.
As for added time, when using a good deep blind structure, I disregard re-buys (typically only ~25% of the field size), but I usually add half of the expected aďd-ons (typically 90% of field size).
So for 16 players, the calculation would be ((16 × 20k)+(16 × 10k × 0.9 ÷ 2)) ÷ 20 = 19,600 as the big blind amount of the final blind level of the event. Note that this is only marginally bigger than the base (16 x 20k ÷ 20) calculation of 16,000 with no add-ons, and basically identical if you added re-buys into the equation: (16+4) x 20k ÷ 20 = 20,000.
In reality, re-buys and add-ons will generally add one blind level
at most, but usually they still just follow the basic end-time calculation guideline and don't add significant additional length to the event.
It looks like I might need at least 25 more 1ks and 5ks. I'm thinking I will need to
lower the starting stack or order more chips.
Ordering more chips is always the answer.