Games that I've played enough to form a valid opinion of that go largely unnoticed:

Rygar I popped the game in on a lark, and was so engrossed in the game that I had to play it through to completion.  It's definitely one that you need to pay attention to the manual though, it's pretty easy to get lost and confused.

Kid Niki: Radical Ninja This is one hell of a fun arcade port.  It's one of those games that you can pop in, play for 15 minutes and either finish the game or not, but you have a ton of fun in the meantime.

Bump 'n Jump Another game you can pop in for a quick run.  Doesn't matter how far or well you do, it's fun regardless.

Dr. Chaos I've been playing this for a few days now, and it's reputation is not deserved.  It has some of the best music I've heard on the NES, and a great title screen to boot.  The gameplay can be a bit frustrating...hit detection on the knife is pretty terrible...but it doesn't completely destroy the experience.  It's just a matter of finding your way around the game, and once you do it's not only easy, but fun as well.

I'll post more when I think of them

Faxanadu the zelda 2 clone is a decent game underrrated game.

The music and gameplay have a medieval theme. The game seems very dark and sinister to me and is worth checking out even though Zelda 2 is much better. 

I guess every bastard that is out to kill you in this game is "the" aforementioned spy.

Maybe you are the spy and therefore the hunted

it should have been called Hunted Spy

I agree with every game you listed except of Power Blade 2. While the first one had an emphasis on exploration (which I felt was its biggest strength), Power Blade 2 is just another "A to B" jump 'n' run. Atleast the graphics are nice and the music kicks ass.