46rh questions

1. The factory low/reverse servo is fairly thin and can crack.
The aftermarket accumulators often have 2 rows of sealing rings and are billet instead of cast.
(Not needed for your purposes)

2. Not cracking under big loads is their purpose.

3. Again for your purpose stock is fine.

4. Instead of a blocking rod install a TF2 stage 2 shift kit.
As mentioned the rod eliminates cushioning of the shifts.

5. You don’t need a cooler.
Spend that money on the shift kit.