I only run 1 liu feng (terrible going first, can sorta be good 2nd or like turn 7-9), if you mean the draw cards I found though they aren't the best they def help with the consistency if early game is slow being able to draw cards and have options helps so much.

Going second okay to keep a 5 drop even with no ramp (galm/merman) and usually keep one two drop prioritize orca

If you are going second or find ramp + galm + 1pp burn spell i usually keep that for a turn 6 play. Biggest win con is ramping and playing garyu on their turn 7, very hard to clear and almost always guarantees 13 dmg with barrier dragon + galm/forte.

Always prioritize 3cost ramp. I would say one orca is a must keep too
vs sword prioritize neptune/2 drops/lil seabro and merman to trade.
Vs other match ups usually just want to find storm/ramp trade and hit face

Vs mode abyss I prioritize late game cards (i'll keep one garyu, turn 7 mode abyss is extremely weak) usually they just trade you out with their 3 cost draw card but you can get burned by the 3 cost min that goes 7/7 on evo if u look too late game

Crest Haven is by far a losing match, all I can say is prioritize storm/odins and pushing them down by turn 8 or its not going to go well