Not really feeling rushed, at least not recently. The first set of quests had the 99th penalty and after it failed we knew that failing 101 means Ragnarok. That part was already rushed since the concept was introduced. Under got a proper introduction last arc and there was some extra info about them and God last chapter.
The manga is doing very well in Japan, so it's not taking drastic measures to avoid the axe either.
About the traitor, he got the most development after Andy, Fuuko and maybe Chen. At least it was always established as a generally nice guy, a parental figure to Tatiana (he shot everyone except her, by the way) and a lot of hints that he was blind. The fact that these quest were open for everyone also means he didn't need the Union at all. If he had betrayed them earlier he would have automatically failed as long as there was a single quest that required more than 1 people from the roundtable (he even says it out loud "open to everyone, so here it is").
Maybe if the author had starter with something like 97 or 98 penalties there would have been chance for some more developments like some explanations on artifacts and more fleshing of characters.