Hello,
Band Steering tries to move users from the more congested 2.4GHz frequency to the less congested 5GHz frequency.
Load Balance will move clients around between access points in the load group to try and get a better distribution of clients per ap. All access points in the group should be located in the same general area like a large conference room, not network wide.
Load Balancing may help but if you have "sticky" clients you may want to look at using the probe suppression feature that was added to the 9.21 track of code.
https://gtacknowledge.extremenetworks.com/articles/Solution/Issues-with-clients-staying-with-an-Acce...
Doug Hyde
Director, Technical Support / Extreme Networks