Imo, the "balance" changes and stuff they made suits low rate server. With mid/high rates most of crafting/custom stuff THEY MADE doesn't make sense.
Also add this, high rate would demand too much content to add with having limited time to release stuff or people will quit. After 2,3 weeks people would quit the mid/high rate and owner need to add new content, new content and new content with new editions. There's lot of newer tibia clients that fulfill this concept with huge damage numbers and a lot of custom content created for mid/high rates which do not reset