Seeking for advice: Should I upgrade to TH9?

I am at TH8. I have all my defense buildings upgraded, and skull walls at 104/225. 4 of my builders are working on mines. I am leaving one builder to up the walls.

Troops that are not upgraded yet:

Valk (Llv.1)
Wall Breaker (Lv.4)
Goblin (Lv.4)
PEKKA (Lv.1)
Heal Spell (Lv.4)

I am thinking to stay at TH8 until all my troops upgraded. But most of my friends go to TH9 w/o upgraded troops and they are doing fine.

So right now I am struggling if I should follow them? Or, finish all before moving up to next level?

Any advice will be appreciated. Thank you.

Personally I think you should go to th9 ASAP. Soon you will have builders doing nothing and that is just such a waste of time. You have already gotten up the troops that you will use the most.

I went to th9 a bit early due to having maxed my walls so hade nothing to use my gold for. I have never looked back, I find the new stuff at th9 make such a big difference and I have no problems farming here.

While you upgrade your th I suggest doing as many walls as possible, since they are most effected by loot penalty due to no build time.

Are your defenses maxed out? If you're going to ask me, my answer will be to max everything out. But I think completed level 7 walls, maxed out defenses and elixir troops(with the exception of dragon and PEKKA) and spells will do. You don't need to max out DE troops. Just get them to whatever level you can afford unless you plan on using Balloonions or hogs.

From my personal experience i would say max everything including troop level since the loot penalty when you reach th9 will be a fair difference between what you're getting now, saying that the loot at th9 ist bad just wont be as good which is a given anyway.. so yeah basically max everything and save yourself the hassle of being behind on th9 when you really wish to be doing the newer upgrades you can do at th9 instead of the ones which you unlocked at th8..
And yeah dark troops arent that much of a worry just focus on the elixir troops and levelling up heroes!!

To my mind, it doesn't always come down to maxing everything.
I'd say :
1) Look at your attack log ! Multiply the loot you get from TH 8 by 0,9. Multiply the loot you get from TH 7 by 0,5. That's what you'll get as a TH 9 in your farming range. If you feel this loot's still comfortable, yeah, go for it. If you make most of your loot on rich TH7, forget about it.
2) Keep in mind that a rich TH 8 won't be raid by a TH 10 because of the loot penalty. A fresh TH 9 will ;)