Bookshelf speakers for a NAD C368 integrated amp

Recently purchased a NAD C368/BluOS integrated amp and looking for bookshelf speakers that are a good match. Current speakers are Celestion SL6si that I have had for ~ 30 years which are acoustic suspension and very low sensitivity. 
Music listening ranges from the likes Mark Knopfler to Nora Jones, etc... I’m 69 and tired enough, so nothing too fatiguing but not too laid back. Any suggestions appreciated but no more then $1200. a pair.

thanks,