I recently went through FF1 on the GBA again, and it's so much easier than I remembered, mainly because I figured out about things I didn't know before. I hadn't realized that Temper can stack, and I also didn't know about how you can use items to cast certain spells. So most boss battles consisted of my Ninja casting haste on the Master, the Master using the Giant's Glove on himself, and both the Red and Black Wizards casting Temper incessantly while the Master goes on to pummel the boss. Even Omega went down fairly easily once I figured all that out!
What's your typical boss strategy? Is it the same through different versions, or does it depend on which one you're playing?