Architect1776 wrote:
You have an excellent camera.
Perhaps as a suggestion, rather than waiting to arrive at the destination, that you put the 35mm f/2 DX lens on your D5300 and go to darker lit interiors (Local Catholic church for example) and take non-flash photos. Then you will know ahead of time then if it works for you or not.
All can sit here and pontificate and speculate but only you know what works and is acceptable to you.
So do the simple test, 10 minutes at most and you will know.
Best suggestion and worth the investment of 10 minutes before spending $1800 for a new camera!