As for lv, I've never heard about anyone having problems with it. Ho ever, it's always better to tweak settings to Your device "liking"

Ignore nice load mean that device doesn't go up in frequency tree (for example, from 500 to 600 mhz) on momentary request, that would result in device going back to lower frequency after moment or so. It's better to keep it enabled.

Up_threshold is percentage of load at which device would scale up. So, higher it is, latter the device will scale frequency up.

Sampling rate - If i recall correctly, time in uS in which device "check" for load. Lower sampling rate = faster response to increased load, but may also increase unnecessary jumping. 200000 is 0,2 second, so it should be ok.

You can get explanation of all parameters in wiki.