No, I would prefer that the Shield of Balduran never even existed. The only possible reason to use such an Anti-Beholder item is if you wanted to make a party of nothing but Warriors, who would get creamed in a Beholder fight. With such a group, there are two alternatives:
1) Come to grips with the fact that Warriors suck against Beholderkin and give up on the idea of EVER killing them.
2) Use the Shield or the Cloak, and get many thousands of EXP for walking around and maybe hitting something every once in a while.
Even if you choose Option 2, the Shield is still unneccessary, the Cloak will more than suffice. There's nothing wrong with putting off the Unseeing Eye until Chapter 6.

Archers are actually much better melee fighters than people give them credit for: Sure, they can only put 1 star into melee weapons, but as compared to a straight Ranger, all that means is a single point of THAC0, 2 hp of damage per hit, and an extra 1/2 attack per round. You don't see people complaining about Minsc's poor melee abilities, do you? True, an Archer's armor possibilities are limited, but there are some really excellent Leathers out there, especially in ToB, and Archers can still wear Shields.