Green Sunfish - don't get very big, don't spawn often enough to be as good a forage for bass.
Redears - don't spawn as much as BG, but if you catch any, put 'em in for growth potential and snail (& hence parasite) control.
The other Lepomis species have no big negatives other than smaller size that I am aware of. Many have (localized) fans due to their attractive appearances.