Rotosound BS66 - Different tone in every string?

I could not find anything related to this using search. Please excuse if it has been discussed.
Well, after a very, very long hiatus I'm slowly getting out there, playing again. Being older, I probably analyze thing a bit more than when I was younger...

I got the BS66 strings because I realized that having a heavier "E" would allow me to easily detune and keep a reasonable tension. Having a lighter "G" would give me more flexibility for bends.

What I find is that, when playing scales, the timbre, the tone of the notes is significantly different... almost like on the old, OLD Pbasses, with the very loud "A" string. Is this usual for these strings? As it is right now, I tend to play certain phrases on a single string, rather than playing across multiple strings. I kind of appreciate the different 'colors', but I'm curious, it this really a "thing" with a heavy "E" and a lighter (regular) "A"??

Thanks!

Diego