Guardian Legend!!! And Faxanadu and Actraiser only the first game tho after they took out the overworld elements it sucked. And Soulblazer. Was that part of the Actraiser world? It sure looked like it.
Actraiser 1 was vastly superior to 2, I agree. Not only did 1 have the Simulation aspects, which made you feel like you were really a deity in the world, but also it had better gameplay/controls in the action stages. 2 had good music and graphics, but the character control was very clunky and odd, and it felt like a slower game. Having a slow character but fast enemies is a bad idea.
The reason Actraiser and Soulblazer look so similar is because they were both created by the Quintet development grouop. As such, they have similar sound effects, similar fonts, and possibly similar artists for the tiles/sprites.
Another reason people think of Soulblazer as a tie-in to Actraiser is because in Soulblazer the hero is an angel who answers to the "Master". And in Actraiser, the player was called the "Master" by all the characters, since he's a God. Thus, one can say that the angel in SoulBlazer 'might' be following Actraiser's God's command...
SoulBlazer has two pseudo-sequels. Illusion of Gaia is the second SoulBlazer game, and Terranigma is the third SoulBlazer game. They have allusions to one another, though I'm certain they take place in different worlds. The theme of souls, the environment/nature and humanity are touched upon in all the three games.
**is a big Actraiser/SoulBlazer guy**