I don't think the house systems are really all that different, honestly. It's not like a 6th house sun goes to a 10th house sun. It's just somewhere around the 5th, 6th, or 7th. Which are all houses that lead into each other. The 1st, 2nd, and 3rd house are all very different but they all have to do with the self. So if you have a planet that's jumping places in the 1st, 2nd, or 3rd just know that it's affecting the selfish part of your life and that's it. Don't stress about it.
My Saturn is in the 3rd house in placidus, 4th house in equal, and 5th house is vedic. Saturn in those houses all mean different things, but essentially, saturn is restricting the value to the self area of my life (I think the houses blend together). 3rd house is how you communicate, 4th is who you are at home, the 5th house is your expression. Anyone of them fit for me. My Saturn aspects my Sun, Moon, and Mercury which very much reflects having Saturn in the 3rd, 4th, and 5th. 3rd and Mercury are kind of the same thing. Moon and 4th are kind of the same thing. 5th and sun are kind of the same thing.
I find that the same themes in my chart come up no matter what astrology interpretation. The themes that are random are probably just not important (I've used chinese, sidereal, western, placidus, equal, whole sign...)
Yes they're all a little different, but who cares. Each astrology is a different piece of the puzzle and you gotta put them together to get the best info. Sidereal is like destiny, western is more psychology, chinese is just something else and the house systems – I'm not sure what each of them mean LOL... They're just different ways of figuring out you. A great thing about different house systems is that the planets that don't change houses even after trying out different systems definitely mean that they should be where they are. That's a piece to figuring out that one main theme of your chart. Like my neptune is 100% in the 1st house.
I think the key to different systems is to try and figure out what the chart is trying to tell you about who you are. And you can definitely find it when looking at all the different forms of astrology. The things that change or you can't understand are probably not that important because the things that are important probably don't change. Or maybe it's saying that your personality can be either of those things; it's just up to you to decide.
I think it's weird that people try to understand themselves and then try to fit or mold a chart to fit their personality when actually the chart is supposed to help them understand themselves.
Astrology is loose and fluid just like your personality.