I'm not entirely sure of what it is you're trying to say here, But there needs to be continuous adding of new champions to this game.. I dont think adding a new Lego that is "bad" hurts anything, as this is subjective for everyone, and if you think about it, Plarium will continue to introduce new champions and abilities while doing this with respect to rares, epics and Legendaries.. the current balance of all rarities of champions needs to stay  pretty much where its at now, otherwise the risk of deflating or inflating the value of the main components of the game, i.e. sacred shards, which have pretty much been the same amount forever, becomes an obstacle. And without financial support from players, the immense detail of updates that we see will decline, not helping the player base grow and probably influencing it to decline as well. 

I guess it's a thing about chances. If you get every month new champs, (especially legis with low stats) The chance to pull a very good champ goes against zero. If you have 100 chanps in the pool or you have 200 champs, the chance will decrease with the amount of champs, because there are some key champs and to get them is almost impossible.

This is a game of patience.  It takes time, time, time to get the champs, gear, resources that you need.  When it does come together, its great. I remember when I pulled Duchess Lilitu.  I only had a few shards.  And that day it worked for me.   

It's not about time, it's about chances dripping down and down and down.... there are too many champs for using as fodder and every month ther will be more.

The recent fusion champs have all been good. I wouldn't mind getting them from shards as did not do the fusions.