Recos for entry level Bookshelf speaker $400-750 for 21yo nieces first system?

Looking for recommendations for a bookshelf speaker for a system I am buying my 21 yr old niece in DC. Will be used for all kinds of music, much from IPhone via Bluetooth or from Mac. Speaker should work on a shelf or tv stand so port forward or be closed. Amp will be NAD D3020 or similar small form of 30-40 w RMS.  Not necessarily audiophile but good musical sound. Have read about PBS, Elac, others. I live in HI so can't hear any of these. I appreciate any and all responses.