The final exp x3 stage is not a good idea.
I've seen on classicus and other servers at a small exp rate, people were able to quickly 150-160 lvls.
If want a long-term server this need very slow exp rate with very good loot rate.
I suggest something like this:
1-8 x7
9-19 x2,5
20-30 x2
31-39 x1,5
40-50 x1
51+ x0,5
magic lvl x1
loot rate x8
skills x4
No remove soul system becasue.
You will not be able to manage bot farms that will be massively created at such a low exp rate.
At a high loot rate, people can buy runes in stores that's enough.
You can remove strong monsters like Warlocks or demons and replace them with other weaker monsters, people will
be forced to expose on weaker creatures and will longer exp to high lvls.
By the way, you could add new outfits to buy in the store or perform quests on costumes.
I know a few people who do not like the outfits available from newer versions of the game.
Personally, I do not have anything to this.
But if you want you can make new outfits medivia style or new unique other.
On such small lvls will be great fun I'm sure.
Because people will not run all the time on mana shield like possessed, because it will not be beneficial for them.
It's not my movie that's just for example ^^
Take a look at the example of this mastercores edition where exp rate was at a similarly low rate.
Can you see here ue spamers and 24/7 play on mana shield like a on many ots servers?
Then small teams , can quickly kill a few opponents and run away when bigger team coming , because no waste much time to destroy mana shield enemy players much time.
On old Tibia, every better player knew that utamo vita is almost like a death sentence.
Unfortunately, not on ots servers where pvp system is stupid and completely different.
But at such a low exp stage I think that wearing a 24/7 utamo will not be profitable even with a larger loot rate.
A few shots of sd balls would make the opponent not have mana on spell haste and then he wont like to use such practices as mana shield 24/7.