In order to utilize Cyber Esper’s effect, you must protect it while it is face-up Attack position. One of the ways is to use Ojama Country to reverse its ATK/DEF value so it will gain 1800 ATK instead, but this will require another Ojama monster on the field. The other option is to use Gravity Blaster to increase its attack every turn. Other than these options, Heavy Mech Support Armor and Machina Peacekeeper can be equipped to this monster for protection, so that if this monster is destroyed, Heavy Mech Support Armor or Machina Peacekeeper would be destroyed instead.
While being able to look into every cards drawn by your opponent may give you insight into their possible strategies, it will cost you resources just to protect and support this monster. The trade-off isn’t that beneficial therefore this card will not see much plays in current met
Weak ATK value makes this monster susceptible to be your opponent’s primary attack target.
Tips, Related Cards, Rulings
Reveals your opponent's hand
It should be "As long as this card remains face-up on the field" duh...