Make defenses scale with % HP and Level

Read suggestion for TL;DR.

If you've been following the meta you know that in order to successfully play ranged DPS classes like Corsair you'll need to HP wash to effectively survive end game bosses.

I'm not going into details and numbers here, I'm going to focus on the arounds of the washing mechanic and its current alternatives and what can be done to improve them.

Lets start with the obvious one: HP challenges
If you compare this new system to HP washing this isn't very attractive, lets be honest.
This system promised to allow new players to skip the waiting for vote cash to stack up and start playing now without washing but the numbers don't quite add up.
The HP challenges system compared to washing is low key weak and long and wont get you even close to the HP you get from washing making you rely on HB which is not always viable and you also lose your ability to wash so you can't supplement it.

Equipment
You can be a good player and collect all the cards for that juicy tier 10 monster ring, you can scroll pet HP equipment, also the Ellin ring is nice. but lets be real after researching I came to the conclusion that you can probably get around 1.5k HP from equips which is nice but those are rookie numbers for late game bosses and if you wish to have more you'll need to sacrifice damage which is not ideal for an attacker.

Back to washing
This post is not about making washing easier and I'm against such mechanic in general, considering its history being an exploit that was never patched by neckson because it was making them fat stacks of cash and now its converted to vote cash sink, ohh the legacy.

High HP as a ranged DPS character is currently a luxury, you need millions of vote cash to HP wash and you probably need millions of mesos for INT gear as well while also probably sacrificing early game damage by putting AP into INT.
So you'll need to play the game for a 2 years probably to reach to the point where this is achievable making the gap between new players and legacy players even bigger.

So here are the problems I found:
1) The server is relying on HP washing to sink vote cash.
2) You need to sacrifice all your early game so you have good late game.
3) You need to be funded meso and vote cash wise to convert MP to HP.
4) The HP challenges alternative is weak and not as rewarding as washing in the long term.
5) Defense stats don't matter.

To increase your damage output, you can scroll some gear with stats or raw damage, its worthwhile because it scales really good.
But its not true for HP or defenses because of low return on investment and missing out on damage.

Suggestion:

Having more defenses currently doesn't affect your damage taken significantly and this is where we might have an opportunity.
Having defenses scale % damage taken and possibly with lvl as well instead of flat values will make HP scale better and also opens a possibility to change how each class scales with said defenses. Also wearing high lvl gear will be much more incentivized because of the base defenses you get from them.

So the sweaty HP washing folks who can afford it can wash away to their content (remember, its a luxury, I mean exploit, no, vote cash sink) while players that opt for the HP challenge system don't miss out on washing and scale for late game while having vote cash can be freed up for cosmetics, teleport rocks, owls and safety charms.

Vote cash sink
I saw a few suggestion and my favorite is create limited time cosmetics that are rotated every month that can either can be bought directly or though cosmetics gacha tickets.

This means much more effort for the staff which makes me feel like this won't happen.

Feel free to add your take, suggestions, numbers, clarifications and ideas