You want good sounding songs? Then you’d best leave these mixing methods alone.
Listening to the solo usually does more harm than good. Especially when listening to individual signals, one tends to make the signal fatter. In the overall context, this is usually not advantageous.
It should rather be done for each instrument. When you listen to the best mixes solo, the individual signals usually sound thin. In the overall context, however, everything fits together. Too many fat individual signals destroy the mix.
With too much compression you take the life out of every song. Especially on the sum, you can kill a good mix out of false loudness ambition. Too much compression sounds depressed and mostly flat. The bass has no life anymore and the highs sizzle. Kick no longer sounds powerful, but thin and “pops” rather than “kicks”.