So I understand LT is the most important OL but what position would come in second for you to fill?

Depends on the team build. In this game typically the role of both tackles is flipped, with the left tackle being good at run blocking since the good runs go weak side. A passing team probably right tackle, running team I personally like centers and interior oline

Your best Pass Blocker should be LT
Your best Run Blocker should be RT
Your Fastest Run Blocker should be LG
Your Strongest Pass Blocker should be RG
Your best INT, DIS OL-man should be C

Reasons
LT = pass protection. The better the protection, the better chances of completing a pass
LG = Pass protection is a plus, but most successful runs are to the left side. Need to have someone get to the second layer of LBs and DEs to seal that extra yard.
C = The QB of the OL. Needs your smartest and best disciplined, as well as your best all-around PB/RB OL
RG = Many Teams like to match their best Pass Rushing Ends against opposing Teams RT (Strong RB but weak PB). Having a strong PB OL at this position can assist in delaying the DE from reaching the QB

Just food for thought, and not downplaying the importance of the OTs. However, in my experience a top notch and balanced Center is indeed a great value in the building of any offensive line. I have always seem to be fortunate in most regards to drafting or finding above average centers. Generally, the are better in value (even if undersized compared to the other lineman) since their careers are 2-3 seasons longer. And usually, they are more versatile and can be moved around to provide more depth as they gain experience playing in multiple positions. If their blocking skills are adequate. But trying to play a OT or OG at the Center position that has limited short snap attributes can be a hazardous situation, so be aware.

Don't underestimate the value of acceleration in your running game.