Kael

How about smaller, but clever enemies? Human height monkey robots like the spider/capuchan monkeys. But make them tricky or annoying. They can disable your trip wires or even place them against you. Imagine fighting a Stalker and all of a sudden, a hostile blast wire goes off... Winding your way through a cauldron and you stumble into a net trap. Cleverer enemies can be just as interesting as bigger, if not more so. Plenty of water type encounters can be made. Riding a robot dolphin, fighting off swarms of manta ray robots, diving into a wrecked ship and a shark robot lurks around the wreck... Or even an encounter while flying through spire like mountains, being pursued by a Stormbird.