How are the spice integrations for kicad now? I haven't used it in probably 10 years so I'm not sure where it's at anymore. I also had trouble using it for laying out traces where length/resistance was critical (high frequency signaling). Altium has been the only thing I've touched recently, but I also rarely do circuit design now, so a "friendly" interface is nice. That's why I prefer using fusion 360 to solidworks or nx.