Yes, mid-fi is an unfortunate term only coined because of the escalating prices of newer phones. 'Mid-price' is a far better term. The fact that phones like the HD600 and DT880 can be had for a quarter or even a sixth the price of your LCD-2s and HD800s does not mean they sound proportionately worse. A DT880 with the right amp is capable of reminding us all that for many years it was Beyer's flagship, and the fact that it can now be had for $200 on a good day does not mean it's a typical $200 headphones. I have the Pro version and on a good recording I'm frequently wowed by the realism of the sound. I daresay many HD600 owner could say the same thing.
We need to get rid of 'mid-fi'. From now on it's 'mid-price'.