I actually think Allen, Zimmer, Luplow, Naquin, Mercado all have a minor league options left, so no need to worry about losing them if a veteran wins the job. The first cuts will likely be one of the pitchers, aka a Taylor, Cole etc, then maybe a Moroff/Stamets after that. I am not worried about the end of the bench since we have a bunch of equal ability guys that way, we just lack in a sense proven 1st string guys. Also I think pitchers Karinchak, Sandlin, Civale, Kaminsky, Chiang, Hill, Hoyt could also make this roster sometime this season in the bullpen if they are pitching well and injuries/guys are struggling. Taylor, Cole etc should make it through waivers and could stay here in the organization so we really don't lose anything that way by outrighting those guys more than likely.
My guess is at the moment, We will keep Luplow, Naquin, Martin and Allen out of camp with Bauers playing some in the OF. Luplow in LF, Martin in CF, Allen in RF and Naquin as the 4th. That though still leaves us weaker to lefties since we cannot avoid the fact Naquin and Martin haven't been proven to hit lefties in their careers. So my guess is a RH like Jones actually is a better fit overall as an OF, but Span is way more proven than Naquin as well. That's my personal evaluation.
This time of the year, the end of the roster gets shuffled a lot, so its actually on the surprising side it hasn't been a lot more than it had this season. We really won't lose anybody by getting the veterans honestly since we will just end up cutting the guys on the roster bubble anyways. The only guy that's someone we could lose is Plutko, who will likely be not much more than a 5th roster, long man in MLB.