Astro

[heuheuheu]

get at least 3k block, else leave it

[akisakura]

take off block
block astral doesnt simply increases the chance of block, it just decreases the damage while blocking,
you can have a nice block rate with gems and refined equipment too,
so ill suggest u to replace block with goddess blessing

Total Block points vs Chance to trigger
111 5%
447 20%
862 35%
1386 50%
2100 65%
3219 80%
4605 90%
5990 95%

Block value enchances both the trigger chance and the % dmg recived

The problem with block is that it suffers of diminishing returns, meaning the more you have the more you need to make it proc.
And also, has treshholds, you will notice difference only if your reach the certain treshold (aka cap for each block trigger value)
Example: Between 962 block value and 1386 you will see no difference (lets say you have 1200 block points).
So this makes block not desirable to push unless you can reach the next cap for trigger rate.

Are moments in long fights when i prefer block instead of godess as for a knight with decent defenses and alot of hp, the heal triggered by block can save a battle (see 3500+heal/per block or more). If you get hit low, you can basicly keep your hp up at all times as for bg, your strategy will change as you will move in front of your troops and allow enemy troops to heal you with tiny hit, thus making block more valuable.

A godess at lvl 7 provides 21% dmg reduction (see all kind of damage)but if you have decent defenses and you get hit by 3k dmg, a 630 value decresed in dmg is not much. If you use block, and you get heal low, you benefit more on the long run even if is a chance.
I would say godess is more of a lvl 60 astral (I refer strictly to knight class here).

But if you really want to swap, keep block at a rate where will trigger and swap block astral with godess. Keep the rest of defense astrals.