I use EB cobalt flat 2814, GHS PW7200, Ti flat and Labella Copper white nylon on my previous fretless P with Ebonol board.
Cobalt 2814 sound growl and crisp , E string are better focus/solid than others set. Comfort and well balance tension as Ti flat and Copper white nylon. Mwah sound a bit metalic than Ti and copper white.
If you licking with blooming vibe, you can't go wrong with the copper white (roll back the tone knob and scoop the amp EQ a bit). Very tasty and smooth , even you pluck hard, she has unique fretboard hitting sound. With zero neck relief and low action, she produce a very nice natural mwah. But she has lack output and buzz on full tone knob.
I found Ti create too much bright tone on Ebonol board, the sweet spot tone I prefer is tone stay on 50% and pluck above the neck join area.
GHS PW7200 just..... uncomfortable playing feel , high tension D and G, E string sound worst than stock 7250M string. Tone wise pretty much like stock string but darker. The mwah sound just like metal vibration effect to my ear.
Hopehelp.
Edit.
Above opinion are base on fretless P + bright sounding Ebonol fingerboard, result may vary than other finger board wood and pickup configuration/placement.