Awesome development.
I would argue it ought to be 30 seconds(way more than enough time for normal shots which would get the players actually used to moving), with 2 optional 15 second timeouts per round to be used for backing off and 1 30 second timeout for confounding off the planet/unusual shots(my world).
Get them used to playing the routine shots more quickly.
Once they've used their timeouts, if they have confounding shot, they may just have to pitch out safely and quickly rather than pulling a dramatic over analyzed Jordan Spiethlike shot.
Faster players do this all the time because they are more considerate and refuse to delay the game like certain players will over a possible miracle-rest of the field be damned.
It's ALWAYS the faster player that suffers when there is a pace of play issue as the faster player will play even faster to compensate for the slower one who speeds up just enough to avoid penalty(if they actually do put them on the clock), and is used to and oblivious to slow play scrutiny.