Teach me about Willpower

I'm a Blaster at heart. Always have been. Most of my toons above level 30 are Blasters or MM's.
I've got a few Regen scrappers at high levels.

My problem is, I've never played a defense or resist based set. I'm used to being squishy.

I rolled up a SS/Will Brute, Mr. Valiant, to take Blueside. He's the most iconic looking Hero I've created to date and I'm having a blast.
He blew threw Praetoria like it was wet tissue paper.
However, now that I'm facing Protean I'm starting to struggle.

It was then that I started looking at my build and various builds on here and I just feel lost.

What I'm wondering is; What powers should I take/avoid. When should I have them and how best to slot.

I'm at work so I can't access Mids but the build is level 22 and currently has;
High Pain Tolerance
Fast Healing
Indomitable Will
Rise to the Challenge
Quick Recovery
Jab
Punch
Haymaker
Knockout Blow
Air Superiority
Fly
Swift
Health

Now that I have QR I thought about Vetspecing Health out and getting Mind over Body, not sure why I skipped it really.

Main questions are; What toggles are must haves?
Do I need to take Weave/Tough
Do I need Stamina as well as QR?
What should I focus on slotting in the toggles, SO wise?

Enlighten me O wise ones in the art of SMASH!

Remember, come i19 you'll get Stamina and health for free, so that gives you room to squeeze in Tough and Weave as well, each stacks up well with your Resist and Defense toggles respectively.

I'd aim to have them circa 30 or 35 or so (which should be fairly achievable given you'll have no need to pick Stamina, it'll just be handed to you).

Strenght of Will is pretty handy, if you can afford it. It's great for when you're about to jump into a tough spawn and take a heavy alpha. Plus the crash is pretty managable.

Since you are Super Strength, avoid flight. Hurl and Foot Stomp cannot be activated while NOT on the ground. You want everything from your secondary except Resurgence. Strength of Will is your T9, so thats up to your preference. Build for +HP, +Def, and some global recharge. I would advise against including Jab in your build. With Punch, Haymaker, Knockout Blow, and Boxing from the Fighting pool, you'll have plenty of single target attacks. My current build includes Stamina, and I don't have to worry about slotting for end redux. Quick Recovery and Stamina allow me to run 9 toggles constantly, recoup the heavy end drain of Foot Stomp and Rage crash and Hasten crash.

To answer your questions directly:
1)Every toggle from your secondary.
2)Yes, you want fighting. High burst damage is a weakness of Willpower, the resistance from tough helps a great deal.
3)I would reccommend Fitness, but it's becoming inherent anyway.
4)Slot for what seems obvious. If you have Quick recovery and Stamina, you won't have to slot for end redux very much. Acc, Dmg, Rech are most important for attacks. Heal, Def, Res are most important for toggles/auto powers.

Something very important to note: If you don't have perma-Rage, when it crashes, you will lose 20% defense. That's a lot, by the way. However, if you double-stack Rage, when it crashes, you will not lose any defense. Make certain that you stack Rage before it crashes if you are still in combat. This is the main reason global recharge is so important to Super Strength as a set.

My brute has 45% recharge, 2500 max hp, 33% def to smashing, lethal, negative, and energy, 52% resistance to smashing, and 50 hp/sec regen out of combat.

I think Willpower is a great set if built right. It's very acceptive to outside buffs. I'm able to tank all 8 members of the Freedom Phalanx and do better single target damage than my corrupter teammates.

This is very insightful.

I think I skipped Mind over body in the mad dash for attacks then picked indomitable instead by mistake.

Boxing as a replacement for Jab, hadn't thought of that but sounds like a great deal to me. Since I'll be picking up the fighting pool anyways.

Fly is a must have for concept reasons. Hurl and Footstomp not working while in air won't be an issue for me. I don't even hover blast, preferring to always have my feet on terra firma during battle. Good to note though.

So I'll want Hasten as well to stack Rage. (Makes mental note to add Speed pool)

I've got a SS/SR Brute that I shelved at 26 on Redside when I decided to re-roll him for GR. I monitor my damage bonus so I can see the lovely red crash of Rage. I wasn't aware that stacking prevented this.

The key to WP is to play the set like old school invulnerability. Your survival is dependent on the number of critters around you just like your fury building is easier when you got more mobs attempting to attack you. What I focus on with WP is HP buffs which will make the regeneration better. Set bonus and accolades are key to this. Then I focus on melee defense once I get as much HP as I can since you get almost no smash/lethal defense. Pretty much all the powers are useful in some way. Strength of will makes it where you dont need tough and weave but with the issue 19 changes you can easily squeeze it in without having to sacrifice much. Personally I would hold off on respecing till then unless you got a respec in the bank already.

Get about 30-35% S/L defense and then grab Darkest Night from the GW patron. Between those 2 you'll be effectively soft capped. Add in Dark Obliteration for good measure, and as the added bonus.

my claw/wp brute is amazing, even though I still prefer my Invul I think.

Tohit debuffs can be resisted. All enemies of high rank or higher level do resist debuffs. Versus AVs, debuffs will be reduced to about 5-10% effectiveness.

I recommend going with Super Jump over Flight, Combat Jumping gives defense and can still be used on the ground for footstomp/hurl, after all.