Need help finding upgrades for my RF Inq.

I am getting stuck on how to upgrade my RF INQ. I have about 4 Divines on Console to spend and currently am trying to get to mana efficiency to run Determ, Malev, Skitter, and Tempest. If I run Tempest I know I need to change to a Shaper block shield.

Any help on how to best upgrade my RF INQ next with more emphasis on defense would be great. Thanks!

Few ways to do that. First is obviously the reservation wheels on the passive tree. That's the simplest/cheapest way. Don't forget armor mastery gives 25% determination efficiency

Next, you can use essence of loathing on chest. Deafening essence of loathing is 9-10% mana reservation efficiency suffix. Cost about 1-2 div for a good roll

If you have cluster jewels, you can get a small cluster with the mana reservation node for either determination or malevolence. I suggest getting a 3 node small cluster jewel, each node gives 6% efficiency. This is only 1 div if you already have clusters on tree.

Another way is using enlighten support gem for determination, malevolence, skitterbots in a 4L. Those 3 cost the most so use enlighten with them, and tempest shield in another slot.

Yet another way is shaper influence shield, socketed gems get 20-30% increased effiency.

You can get mana reservation for particular skills in an amulet. For example hunter amulet gives malevolence, warlord gives determination.

One final way is unique/corrupted jewels which can give 2-3% efficiency