Inara's ultimate has a long windup time so before using it make sure to be in a safe spot with enough health to survive bombardmemt. It has an obvious voice line letting the enemies know to focus you so using damage reduction first can help.
Inara with Treacherous Ground will murder your whole team if you are not careful. She can trap multiple champions, allowing teammates to decimate them, and she can dish out some damage too. Consider taking Bulldozer just to destroy Warder's Field.
Your ult goes through shields. against a double shield tank on point this makes their longest cd's worthless. It also goes through terminus' absorb shield. Stunning up both tanks on point and blowing their 15 sec cd's is huge.
USE YOUR WALL! It blocks fatal attacks, (Terminus ult, skye ult, ruckus ult, willow seed, BK grumpy, etc...) Most healers need line of sight to heal. block vision from a single target with your wall and burst them down before their healer can react