I think you hit a key point...especially in Brohm's offense. The offensive line is pretty veteran and I think most would agree that the interior OL are all smart and very capable players...especially Barron. But finding some tackles who could pick up the communication and schemes was highly important and I believe Brohm and his staff made that an incredible point of emphasis.
I think the other key is although Purdue's WR's are playing very well....they are likely not playing their best combination of WR's up to this point. Brohm himself said that the new guys (Wright, Zico, and one of the freshman) didn't have a command of the playbook yet and that has limited them up to this point. Now in week three, you could see more and more of those players on the field which gives the offense more capabilities. If the drops are taken care of, Purdue is likely behind only PSU, Whisky, and Michigan in terms of having an offense that is capable of running and throwing the ball (IU is still very good at throwing it...they are just horrible at running it).
The game against Missouri likely shows really where Purdue stands right now and where the season could likely end up. If Purdue is able to get a W, it is a good opportunity for Purdue to get wins against Rutgers, Illinois, Northwestern, and a potential toss-up against Minnesota and Indiana. A potential 7 win season in his first season that would see 8 returning offensive players (2 are Phillips and Mahoungo and those are replaced by Wright and Zico...so potentially 10 on offense) but loses 7 on defense (returning Neal, Bailey, Jallow, and Theineman but also have players in the 2 deep that have started/played heavily in Wilson, Jones, and Mosley). If Brohm is able to find the pieces to replace on defense for Holt...Purdue could be a very good team next season and likely looked at finishing somewhere between 3 and 5 in the West....also Purdue's first four games are at home and never play back to back away games (have an away game, bye week, and away game though). That's an incredible advantage for next season and hopefully the fans come out in droves to support the team.