Wildcard searches in build name would be nice, either that or have it search as a "Contains" method of search
Being able to select multiple options from the Group type dropdown would be nice. Often I think players are either grouping in season or they are mostly running solo, in either case they would often want to selecting one of: Solo or Group, and then also add in Hybrid to their selection.
load of the page each time I want to hit "Top - week" or "Top- month" or Top - all time" perhaps not the best method. Wait until hitting the filter button to reload perhaps?
As a user I tend to prefer to see "Top - All Time" or "Top - Month". I can imagine doing the week ends up saving the default load time, and improves performance, but this is likely increasing the traffic against this page, if most viewers are like me.
Can't think of anything else as yet. Perhaps other viewers can, if so please comment.