I'd say TE is certainly a weak spot for us- mangum is getting older and both gaines and seidman have been inconsistent.
Also DT is a spot we could use... Buckner is towards the end of his career and we all know what's happened to Kris Jenkins; 2 years in a row ouch
I assume we'll sign Will Witherspoon back, so for now OLB is NOT a need.
And worth a look: Our RB situation could become cloudy in the future... given stephen davis' age and the fact that DeShaun Foster will be a FA(restricted I believe, but don't quote me),we may be exploring other options. Moot point however, if Foster is resigned.
Hope I helped.