You have to think of your worst possible hand and see if it can beat someone's average-good hand
Sasha/Sandro or Chiara/Redra/Belle may have round-winnability on their side but they certainly lack the damage req. to actually do anything drastic....you may get Lucky once or twice and face other poor hands but in the end pulling this sort of hand will spell defeat.
Also Skeelz' 3* are worth packing in, seeing as their 4* are either situational or lack the power to do anything (Greem just collapses in front of certain draws such as Montana or Uppers)...I only ever use your previous deck in ELO for Skeelz
I don't quite agree with the above. One thing that people forget about the Skeelz is that they have another powerful nuke; Snowflake. Snowflake will often gap for somewhere around 7 or 8, sometimes higher. With the right walls, that can definitely win you the game. The odds of drawing either Snowflake or Greem + a couple of great walls are pretty good.
As a rule of thumb, if you have at least 3 hands that are at a huge winning advantage, I consider it okay to have 1 weak hand. The odds of drawing any four specific cards are the same... So that means for every game you will probably lose due to your weakest hand, you will probably win 3 due to your strong hands.
Also, keep in mind that Belle can be really dangerous, especially if you sneak that fury in! You might still be able to get away with a 3-round win with a seemingly poor hand, like Chiara/Sandro/Sasha/Belle.
TLDR: Go for it.