So i started long ago with olympic fencing, and though thats hardly a "martial" art, it did lead me to more historical fencing systems, mostly german longsword and italian rapier. From that came SCA heavy weapons.
At some point in there I started a little aikido, then moved to taiji quan and baguazhang, though im quite new to both.
Thats just the formal stuff though, most of what ive learned is from playing with friends and integrateing what works. Idk where most of my groundwork came from, for example, as thats all learned from various people and systems.
I dont see a problem with useing multiple systems though, fighting is fighting, and different stuff works for differemt bodies and situations. The way my curent body works is not the same as any of my training partners, nor are theirs the same as each others. Seems silly to stick to any one system's rules.