Tap Titans 2 - Should I buy perks? Perk List is here

Should you buy perks in TT2?

If you are rich, then Yes.
No one can stop you from buying.

But if your diamonds are earned by your hard work, then No.
You should NOT buy perks.

You should save your diamonds to buy more important stuff, pets for example.
Some people even saved enough to buy a legendary weapon from daily shop(when they saw a good one)

So how can you get FREE perks?
You can get free perks from fairies, tournament reward, daily login reward etc.

Here are the Perks List and explain (they all have short description, right?)

Make it Rain
A lot of fairies will come out so you can click on them to "Rain" money.
I my case, if I got a reward perk from system, 50% will be this make it rain...
Use it wisely only when you stuck on high level, especially for beginner.
Later on you will find you can easily level up without them. I still got 4 of this perk didn't use.

Mana Potion
It has the same price as make it rain, I think it's over priced. Just refill your mana? For one time? I will just turn off my phone and wait. Maybe late game become useful, but I think they got the steal man skill in late game, right?

Double Damage
It is useful, especially for beginner. If you just started got several hour free time. Spent this perk. But compare to all the other ways you can multiply your damage, not worth to buy but better than the mana one. And in my case. I got a 20-30% chance to get this one from system.

Doom
Another over price item... Summon a monster help you kill titan? it won't even last... Dev should change it as least last for 10s... lol

Power of Swiping
This is the skill I bought it before and kind of regret it. Because I read the description "for MAX speed" LOL. It's not max speed I'm telling you. Still depend on your swipe speed. I found the best way to do this non stop is drawing a big circle on my screen. It won't work on Clan Quest BOSS. And BTW, they updated this skill after I use it. Now if you hold your screen, it will auto attack, but slowly.

Clan Crate
A big money box have lots of gold, you don't have to click on it right away. Check out the Tips section on the right.
The chance getting this for FREE is so low, like 5% I think?
It's so expensive, I hope they can lower the price then it's a good item to help out your clan members!