I actually really like markilleruk's suggestion abour making SoP a permanent that indeifnitely delays your creatures, buffing them every turn untill you decide to destroy it (perm ability). It fits the whole 'patience' theme and also acts as a hard counter to the super OP SoSac. It creates a dilemma - should you lose a turn attacking, or continue to gain buffs? Opens up new uses for inundation, esp to weak creatures like octopus or malignant cell. Maintenance cost also good to prevent OP.
I do not think it should delay or buff the opoment't creatures though. SoP would eclipse sundial if that happened.
Honestly, yes. This is perfect. The SoSa counter really sold it on me, because SoSa is currently pretty much counterless, aside from OHK and antimattering your own creatures. It makes sense for shards to counter other shards.
I kind of think SoG and SoP should switch elements though. Water already has purify and great stalling, making healing best for it. Life has a load of spammy creatures to work with SoP, get rid of the flooding part, which doesn't even make sense, and just make it +1/+1, +2/+2 for life creatures. Plus life shard countering death shard would make a lot more sense.