With an easy to follow guide yo ucan set up your trinity based server. I believe you can edit the level cap in one of the config files like in Arcemu.
It's just my opinion but if you are aiming to make a FUN server the best choice for you would be the Arcemu. Trinity has less bugs and more things working that's true, but it meant to be blizzlike. That means if you want to make custom stuff you should know c++ very well.
I'm not saying Arcemu is better or worse just wanted to tell you that is mroe customizable at least it's easier.
In case you didn't like the PryDev link:
Mangos repack Blizzlike 3.3.5
Trinity Blizzlike 3.3.5
Jeutie's Blizzlike Repack 3.3.5
GRiM's Ultimate Repack v6
And here's an arcemu repack if you want to try:
Beautiful Mind 3.3.5 Blizzlike Repack
And yo ucan find more in the General Releases Section
Still I suggest you to try out Arcemu and if you liked it compile your own one. You will then have your very own server which can be edited as you want.
You can find a step-by-step guide on this page.
Good luck and have fun,