how many first round ( early to mid picks) drafted out of NCAA stuck around in their
D + 1 yr
Guys drafted in the 1st who stayed for more than 1 year
2013
None - No players were chosen in the 1st went NCAA route aside from McCarron who moved to the OHL
2014
Nick Schmaltz 2 years at Wisconson
Alex Tuch 2 years at BC
Dylan Larkin Spent 1 year at Michigan
3 total guys that went NCAA route
2015
Jack Eichel - NHL
Noah Hanfin - NHL
Colin White 2 years at BC
Brock Boeser 2 years at UND
Zack Werenski spent 2 years (including his draft year) at Michigan
Kyle Connor and Jack Roslovic spent 1 year each at Michigan and Miami
5 Total guys that went NCAA route after being drafted (Not counting Hanfin and Eichel)
2016
Henrick Borgstrom spent 2 years at Denver
Trent Fredrick Spent 2 years at Wisconsin
Tage Thompson spent 2 years (including his draft year) at Connecticut
Rileyy Tufte spent 3 years at Minnisota-Deluth
Dennis Cholowski spent 1 year at St. Cloud State, then signed and moved to the WHL
Keifer Bellows spent 1 year at BU and thenn signed and moved to the WHL
Dante Fabbro spent 3 years at BU
Luke Kunin spent 2 years (including his draft year) at Wisconsin
Charlie McAvoy spent 2 years (including his draft year) at BU
Clayton Keller spent 1 year at BU
2017
Cale Makar spent 2 years at UMass-Amhearst
Casey Middlestadt spent 1 year at Minnisota, but was 19 in that season
Josh Norris spent 2 years at Michigan
Ryan Poehling spent 3 years at St. Cloud state
Jake Ottenger spent 3 years at BU
Shane Bowers spent 2 years at BU
So, to sum it up, in the past 5 drafts there were 26 guys that were drafted from the NCAA.
17 of which spent at least 2 years in the NCAA.
2 of which went straight into the NHL
2 of which played one year of NCAA and then moved to play a year in the CHL.
5 of which played 1 year then went pro.
So to answer your question, a very large majority of 1st round picks play more than 1 season in the NCAA...