Actually it would make sense to get rid of the Artist tab.
One may have more need to browse maps by Date and Difficulty. However most of the time when one think artist, he/she already have the name in mind and current search feature can already cater for that. Sort by Artist does not need such a high profile appearance in the tab form, IMO the pull down menu is plenty.
It'll be good to replace the Artist tab with something that's likely to be browsed, eg Collections.
On a side note, I've been wondering about this performance hit (lag) myself. Everytime I choose sorting by Artist my system lags (up to 5s). Other sorting mode (Rank, Difficulty, Date, Last Played, etc) doesn't produce the same kind of lag. I wonder what's taking so much system resources?