Otto Lopez, Addison Barger, and Spencer Horwitz should all be in AAA playing everyday. They still have a chance to be something more decent than an end of the bench player. And would get more value currently getting that playing time.
Journeymen like Lukes or Bernard are perfect for 26th man. You pick whatever one provides you with something useful whether it’s Defense, Speed, or a chance not to be useless with the bat. Lukes is already on the 40-man so he seems like the most logical choice. Although he could just be swapped out for Bernard. Probably lose Lukes on waivers which hurts you depth wise a little bit. You bring Lukes to start you could probably keep Bernard for AAA. Unless he gets a last minute shot to catch on elsewhere.