Sure, you are putting good ideas. In spite of my thoughts about the shield solution It's something worth a try. I recommend you adding some LM desert near Egyptian and Arabian starting locations. Then, play a game with visible map to see what's happening. Ah, about the curraghs. I changed that after having played a standard game with a seafaring civ and noticed that Trireme was useless. Attack 1 defense 1 moves 2 become for a seafaring civ 1/1/3. I did not use any trireme, only that small boats (and I ask myself how that boats could be armed). And I think Alphabet is a non-sense prerequisite tech. Pottery means water-proof containers: it makes more sense.