For character transfers, the server's take on the Inf economy will be relevant. If your character is coming from a server where the Inf is free or massively inflated, moving to a server where the economy is more 'traditional', the transfer could wreck the economy. The same with recipes, salvage, and other things that could be sold.
Possible other things that could be of concern are earning badges and whether the original server gives everyone all the badges and the new one requires that you earn them. Did you earn your Enhancements or were you gifted them. There's no objectively wrong answer, but there is a question of compatibility.
I don't think anyone cares about character level.
Fundamentally, it's an issue of trust and what the rules are on Server A vs the rules on Server B and whether those are compatible.
Well the game used to have character transfers, so seeing that return would be nice.
As to the character and what it is equipped with in terms of enhancers and badges and inf.....there is likely no way to prove if a character was "administratively boosted" vs. earning all the items through game progression.
There are also the haves and have nots, some players will look at any character and cry that said character has something they do not such as an anniversary badge or the notorious bug Hunter badge.
There will always be someone that thinks someone used an exploit or is an AE farm product or used a macro or a bot or something else to reach level 50, 2 billion influenc, have a maga supergroup base, etc, et , etc.
And with game back on emulation and the current i25build having basically everything unlocked for xcept bug Hunter badge which is fine, and an opportunity to purchase with merits the past years of anniversary badges, during anniversary time only, and even shortened the time to o get day job badges.....let's all just have fun and give that giant middle finger to Ncsoft that they so justly deserve.
