Integrating Vintage Audio Equipment With Modern Hi-Fi Systems

I’m currently running a hybrid setup that combines vintage analog equipment with modern hi-fi components. The idea is to keep the character, build quality, and sound signature of older gear, while using newer technology for convenience, efficiency, and connectivity. For those who’ve done something similar — what worked well and what didn’t? Were there any issues with gain matching, impedance, noise, or signal loss when mixing old and new equipment? Do you feel a hybrid system offers the best balance, or does it introduce compromises that make sticking to one era a better choice? I’m interested in real-world experience, not just theory.