First, thanks for being upfront about it. The answer really depends on how much you've used/followed the original sprites, so it would help if you could post a comparison of your character and what you used as reference / source material (I quickly searched with google image, but either you're using an enemy that I can't find, or you have actually pixelled everything and only looked on Chaos Engine as a learning material).
IMO, you have two paths :
- you have the skill and the time to go full original : Do it, and you can claim full credits for the graphics of your game, and can distribute it on platforms that care about copyright (You may also need to avoid using the name "ikari warriors".).
- you lack either the skill or time to do everything: Re-use, recycle, and create the missing parts that help fit everything together. This is not as good as being able to say you created everything from scratch, but completing a game is always something that you can be proud of, rather than having one more unfinished project.
At the moment, this sprite looks nicely detailed, it looks ambitious (don't underestimate the number of poses and angles). Personally I like the colors, you could make the flesh highlights much shinier (80's sweaty muscular action heroes!) but then there would be the issue that when the player moves and rotate the character, the highlights may move all over the place. You're not trying to mimic the technique of mixing greys and colors of Dan Malone, and it's probably fitting for jungle scene. (and considerably easier). Just be careful of readability : Ikari Warriors and Chaos Engine used very simple play-area, often single-color, so the characters, enemies and bullets could be very detailed and still be very readable and recognizable. If you try make your background more pixel-detailed (ie : grass), the character will be less visible and will feel more "noisy". You've chosen a design which is rather dark and un-saturated, so in general it should always be displayed over a light and saturated background.