Biamping has multiple benefits when properly done. That means using an electronic crossover and bypassing the existing crossover entirely. By removing the lowpass series inductor, you also remove the resistance that kills bass damping. It can also add up to 6dB dynamic range simply due to how amp level voltages sum up, so a 2x50W biamped system has the same dynamic range as a 200W non-biamped speaker. That opens up a whole different approach to powering (and taming) things like Klipsch KHorns and Cornwalls. In pro audio this isn't news - biamped studio monitors were common 50 years ago, and I designed triamped and even quad-amped live sound systems back then as well.
As for "3. The following is my preferred solution which is to use a source (DAC) that has some DSP. Purists will hate this idea but that's ok. The DSP allows you to tailor the sound to your liking. Adding a few dB of gain in the low bass region can really make a difference. Again, I'd recommend auditioning something and playing with it for a weekend to see if it solves your issue." I couldnt agree more. Get a WiiM Ultra Music Streamer & Digital Preamp for a whopping $329(!) and you get not only a better than decent streamer and DAC, but a very nice graphic/parametric equalizer as well as DSP tuning. I just swapped one into my office system to help a bass-shy but otherwise spectacular pair of Focals and am very pleased with the results.