Over time it seems the value of a position in the NFL has changed substantially. QB probably has been the most universal choice over all time, yet, once you have one, they are also likely to be the most enduring meaning that other positions become priorities. So, if you have a QB, what is the next best choice or priority?
Corner backs are prized as difference makers, yet they do not necessarily control the outcome of a game unless you have an overall very good secondary. Simply put, you can avoid one shut down corner and have a highly productive offense.
Defensive end is another very important position given the need to produce pressure on the opposition's QB. It is irrefutable that distracting if not outright sacking the passer in today's NFL is essential. One great end can make a difference, although an entire line unit is the real goal.
Left offensive tackle typically protects the blind side of the passer, since most QB's are right handed and face their right, their peripheral vision limits how much they can see coming from the left. Protecting the most valuable and most immediate ball handler is obviously very important in and of itself too. Given the propensity of the passers not to see the left hand side, teams likely use their dominant rusher from this end and thus the best blocker on the offensive line is needed to handle this position.
It seems obvious from this presentation that the secondary unit, defensive line unit, and offensive line unit are premium position groups. Having effective personnel in these positions is of great importance and value.
Wide receivers might be the more individual value position to mention next. The NFL is passing oriented and it requires not only a great passer but a great receiver to gain separation from defenders and solid or consistent ability to catch passes, especially if they are contested.
If you have solid, good, or very good pieces as mentioned above what's next? I think it is the running back. It is somewhat overlooked in the NFL today because typically it is handled by multiple players on the roster as a committee with perhaps specialists - some power runners, some faster, and some better at receiving. It seems less and less likely to find one player that provides all of these skills so a unit of three or more players are expected to offer the team these abilities.
If a really good running back however is available, that offers all of these skills and the physical frame to likely remain healthy over the grueling schedule, it is truly uncommon, and could be deemed an exceptional value. Less roster positions may be required to support this aspect and the one running back offers a variety of skills to confuse the opponent more readily as to the type of play being run.
Bijan Robinson is this type of running back. I think he deserves the Lions attention as their first pick. They definitely can use help at other positions. Corner back, defensive tackle, defensive end, offensive line, and even tight end could use more depth if not truly starting talent. However, Robinson stands out as the lone exceptional talent to provide all three types of offense from the position. It has been suggested he is the type of talent that is a "once in generation," type player akin to Calvin Johnson at wide receiver and, or Barry Sanders at running back.
I support the Lions if they opt to trade down to a quarterback needy team, but hope that they consider and choose to draft Robinson as their top first round pick. I think the value is highest for him, and other talent for other positions of need will be there to bolster the team's ranks beyond the starters that they already have.
Running back on the Lions is also a position of need. Jamaal Williams is 28, and a free agent this year. He had a career season this past year, and I'd like to see him retained, but I don't expect him to repeat the type of year he had as he ages. D'Andre Swift is in the final year of his contract and may or may not also be retained. He has been a great player, but a regularly injured player too. That limits his effectiveness as well as simply his availability. Robinson would seem to likely become the new starter with one of both supporting him.