I have listened to the SF speakers you have. Pretty good loudspeakers. But I would bet the jump from Cambridge to dCS would show you what your speakers are capable off. That can keep you satisfied for a year or two. Save and then jump to a much more better speakers than you currently intend to get. Not sure if you have room treatments. They will make a positive impact when placed properly.
Upgrade speakers or DAC
Next upgrade is going to be either Front L/R speakers or streamer. Current speakers are Sonus Faber Olympica III, looking to upgrade to Il Cremonese. Streamer is Cambridge Audio Edge NQ looking to upgrade to dCS Rossini APEX.
Which upgrade will make the most significant improvement?