I would save my Chase apps and get the BA, Hyatt or Sapphire Preferred cards. 50K UA miles doesn't seem to be worth much...

AX Plat, BA, Sapphire gave 100K, and Hyatt gives 2 nights plus Plat status.

However, this is from the perspective of a UA 1K, where I can rack up the miles fairly easily with the elite RDM bonus. Hotel points can be expensive to get.