Let's go over them in order: Just three mana - Sorin is incredibly strong as he can come down very early
Many players enjoyed how the set truly captured the feel of the Phyrexians from the gameplay to the mechanical themes to the art to the overall look and feel of the cards. And here is one of the lessons learned from that same set: The Phyrexian flavor was off-putting

Ancient Greenwarden Atmospheric Greenhouse Bringer of the Green Dawn Circle of Protection: Green Dryad Greenseeker Emissary Green Fecund Greenshell Green Dragon Green Goblin Green Goblin, Back for More Green Goblin, Nemesis Green Goblin, Revenant Green Mana Battery Green Scarab Green Slime Green Sun's Twilight Green Sun's Zenith Green Ward Greenbelt Guardian Greenbelt Radical Greenbelt Rampager Greener Pastures Greenhilt Trainee Greenhouse // Rickety Gazebo Greenhouse // Rickety Gazebo Greenseeker Greenside Watcher Greensleeves, Maro-Sorcerer Greenwarden of Murasa Greenweaver Druid Greenwheel Liberator Greenwood Sentinel Gysahl Greens Legolas Greenleaf Llanowar Greenwidow Lurking Green Dragon Outcaster Greenblade Rune of Protection: Green Ultimate Green Goblin Wielding the Green Dragon

If they die, get exiled or anything else that removes them from the board, you can instead put them back in the Command Zone, but you have to pay two more mana to cast them - and that cost goes up every time
Though insect tokens arent going to benefit from our tribal synergies, they will be buffed by go-wide effects, are good blockers, and come with a card draw engine in Izoni