Celestion Ditton 66’s. ‘Upgrade’ to modern speakers consequences?

I have some vintage Celestion Ditton 66’s that have had their crossovers professionally recapped and serviced. All speaker units are in excellent condition.

My question is.. what might I gain and what might I lose (sonically not financially..) by replacing them with high quality large/floor standing speakers manufactured in the last decade or so?

My amplification set up is a Yamaha C4 preamp and a Yamaha 2200 power amplifier both recently recapped and serviced.

Source is mostly streaming Tidal or CD player via a Chord Hugo DAC, and occasionally some vinyl.