I don't know, either. I liken it to watching a game of chess -- no sense in judging the first several moves, but I would love to see a glimmer of a strategy if not for my own indigestion.
One strategy that's pretty obvious: it's pretty clear that the front office (in trading McGahee and Spikes) is intent on getting something for higher-level players before they bolt (i.e., the year before their contracts are up). That's great for the future, but it tends to leave some pretty big divots.
Both departures are big losses, but Fletcher much moreso IMO. Spikes is coming off a very tough injury (achilles) and is not as well-positioned for the Bills' defensive schemes.
I do think that LB is pretty deep in the draft pool, and we have players (like Crowell and Ellison) who do fit the defensive scheme. And rookie LBs can definitely have an impact early on.
I also think that we are not done in FA -- a lot of cap room just got cleared, especially in dumping Holcomb. If it's LB, I have no idea. A lot of "people" on the Bill's message boards (which are infuriating) seem to be begging for Briggs -- I don't see that happening.