Hard, if not impossible to judge just on HS over 20 years as earlier poster noted due to such different levels of competition. If you base it on being highly productive/dominant in High School and then being able to demonstrate it again in college and even pros I think you can start to narrow it down. Some great players I have seen over the past 20 years that were all almost immediate impact players in college and most in pros would include some of the following:
QB's Jared Goff - Marin Catholic, Cal, Rams #1 draft pick
Jake Browning - Folsom (set almost all HS records), UW
Handful of guys had magical Boyett type HS careers - Graves at Folsom; Drew Schiller of Burlingame comes to mind who was Gatorade athlete of the year for CA during HS. Also - Pearson of Carmel had over 10,000 all-purpose yards throwing and running and accounted for 117 TD's.
RB's - hard to quibble with Lynch - but also have:
Jahvid Best - Salesian 6000+ yards, Cal, Lions 1st round pick
Najee Harris - Antioch 7800+ yards in HS - playing at Alabama as an underclassman
Ontario Smith - Grant 6,000 plus HS yards 99 TDS, Tennessee, Oregon, 4th round pick Vikings
Maurice Jones-Drew - Great career at DLS, UCLA, great pro career 2nd round pick Jacksonville
Doug Martin - St. Mary's, Boise St.; 1st round pick Tampa Bay
Hard to come up with any better receivers than the two you have but;
James Jones Gunderson, San Jose State - 3rd round pick of the Packers who had a nice career was dominant in HS
Julian Edelman - Woodside - great HS quarterback of undefeated team, played QB in JC and Kent State-- 7th round pick of Patriots with great pro receiving career.
Tight End - Would put Austin Hooper here - DLS, Stanford - 3rd round pick Falcons
Rhett Ellison from St. Francis was also great in HS and at USC and has had a long pro career as a fourth round pick.
OL - All really dominant HS lineman with strong college impact (some in pros)
Andy Levitre - San Lorenzo Valley, 35 starts at Oregon State named All American, - 2nd round pick of the Bills
Carl Nicks - North Salinas - Nebraska -5th round draft pick - all pro with Saints
Many mentioned Williams - Folsom - starter as underclassman at national Champion Alabama and Samia - SRV and Oklahoma
Kolton Miller - Roseville, UCLA - 1st round pick of Raiders
Defense
Lineman
Jared Allen - was a beast at Los Gatos - got into some trouble and lost college interest but had great career at Idaho State and then was a fourth round pick of the Chiefs - played 12 years with 136 sacks in pros.
From the WCAL Jeff Schweiger from Valley Christian was state Gatorade player of the year as a DE and started at USC and Rashard Greene from Sacred Heart Cathedral was unblock able in HS with 45 sacks his last two years and also started at USC - not sure if either made the pros.
Vita Vea - Milpitas - U Washington dominated in HS and college and was #1 pick of Bucs in last years draft
Derek Landri - DLS, Notre Dame and 5th round pick of the Jaguars dominated in HS and college.
Linebackers
Mason Foster - Seaside, University of Washington - 3rd round pick and long pro career with Redskins and Bucs
Cameron Smith -Granite Bay, USC - over 300 tackles already
Kiko Alonso - Dominated at Los Gatos and Oregon - 2nd round pick of the Dolphins with long NFL career
Defensive Backs
Marcus Peters - McLymonds, three year starter at U Washington with 11 Int's and a first round pick of the Chiefs.
Dwight Lowry - Soquel - had one of the best prep careers in Santa Cruz county, All-American at San Jose State - long pro career as safety and corner with Jets and other teams.
