Mirana - Good agility gain and skills, but little else
Viper - Passives still useful, but begins to drop off
Juggernaut - Flexible but lacks total damage/health to fight big carries
Razor - Static Link is still useful, but begins to be outscaled or escaped
Riki - Fantastic DPS, but very squishy, vulnerable to detection
Slark - Useful anti-carry and stat steal, but otherwise lacking
Tinker - relatively low right click damage, but active items can provide a lot of utility
Broodmother - lacking stat growth and skills help less in the late game