I think these could be added for the future:
1. Chance for higher tier runes
This used to be the case, but to stop the server getting crammed with them the drop rate had to be quite low. GM changed it to drop smaller ones but at higher frequency. Lots of small wins feel better, drip feed of dopamine. They've certainly been better this event than previous, but I agree it's an important area that GM needs to monitor and keep tweaking
Yes! They are there, but very rare. Careful Kev making an appearance along with a carpet of gems and oils is a key gold sink. But seeing a few more orbs would be lovely
3. Gold bars (not too common but not too rare)
No objection to that as long as its rare enough, the gold/gg exchange rate is a really hard thing to balance so we need to keep a lid on too much gold flooding in
4. Increase drop rate of Mythic item that gives mythic essence, its so rare i dont remember its name but i received 2x small mythic items that gave me a tiny amount of essence
You're thinking of MythicVessel. They do give a bit of mythic essence, but the amount of mythic essence on the server is generally pretty high, so I don't think any adjustment is needed here. You will collect a lot of trash mythic items and sources as you go along, salvaging those will be your main source of mythic essence, by the time you've done a couple of these events you'll have more than you know what to do with
5. New item called an Exp Gem or Orb that grants 5 million exp (not too common but not too rare) this would be good for alts or new players that join and purchase gg/gold to skip some of the harder levels.
From feedback I've heard, at lower levels main issue seems to be obtaining the right kit to kill mobs at your level. Getting another free boost is going to exacerbate that even further. In recent times early levels have been made a lot easier and higher levels have been made harder. If anything I'd say something that gives 1% rather than a fixed amount would be a huge help to the most committed players
6. More Arcamon (L) food drops, i personally didnt see a single one drop but my friend that spent almost double me did manage to see 1 which is a bit lame for how much is spent expecially when the food isnt that OP and i wouldnt be game breaking to let more of them drop in the gg cave.
Strongly agree with this one, I'd love to see that. Although the gg pet foods I suspect are a good income stream for GM so I'm not sure he'd be too keen to increase these too much
7. Option to join the Fire Crystal GG cave as a group (level of monsters should be based on party leader) this way we can spend our GG together and get more exp than we would have solo assuming both players are donating and buying crystals.
In the higher level caves (top 2 tiers) there are pillars that can be used for this purpose. Yes there is pk, but it's a demon soul sink and pretty popular
8. Event tickets that drop quite often which a specific amount can be exchanged with an npc for a variety of items including the above, orbs, mythic essence item, Arcamon Food (L) etc. I like this one because even if you get screwed over with the drops above you can build up tickets for guaranteed items.
Interesting idea, definitely worth exploring. My only concern is that it might be a bit too complicated. You're lucky if most people read a big red message in their face, explaining how a new thing works is always a pain, even if it's something as simple as a token collection lol
love the fact its getting alot harder to level now 
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