Many filters would be better and even more useful if they had levels

I have seen that on most filters there is a lack of controling the brightness, black and white points and contrast.

SUGGESTION - INCLUDE IN SOME FILTERS ADJUSTMENT OF
Brightness / Contrast AND/OR Levels

I think that many filters would be better and even more useful if they had a brightness and contrast component and also a levels controls added.

Would adding this two components to the filter make it less efficient and be a problem?

Would make it less clean built ?

Why there is no interest in adding this controls to the filters if they could need it?

I think that adding this would be very interesting and useful on lots of filters that are already good but could be even better.

One recent possible example is Romancing The Gorilla by Carl that gives many times depending on the source slightly too dark results for my taste.

I know that you can make a postwork after in Photoshop or any other similar program, and you can change the brightness and levels AFTER you have done the FF effect, BUT why not do it already inside FF?

AND this is much more important IF you are using the STANDALONE version of FF, where to be able to modify these ones you will have to open another software and load the image to do it.

Of course that I am not suggesting that this should be included in all the filters, JUST only in those that the possible results could give probably too dark or too light results, or with not good contrast.

CONTROL CLUTTER?

I do not why this is not used more, and thinking on usability, perhaps the reason could be that the intention is to put less controls as possible and keep it simple and clean, BUT I think that this could not add much to the controls list, and would really be a much improvement and very useful on many filters available.

MY FILTER ALREADY INCLUDES THIS

Images Bands Collage

In the only one filter I have released until now (I will release more soon) I have included this and it changes much the result and would not be the same without it.