I should point out that from books I see, Trade Gothic has Light, Regular, Bold, and Bold No. 2 weights (that is the term you were looking for, I think), with an Oblique version of each. It also comes in two additional widths: Condensed and Extended. Both have a Bold & Regular weight, and the Condensed has both weights in Oblique form too. That makes a total of 14 fonts.

However, I applaud the idea of looking for a fresher alternative to a design from 1948. Eduardo suggested Benton Sans from Font Bureau (which I think is a retail version of Benton Gothic, a 1995-2000 Font Bureau Studio Font, available only by special licensing from them). Both are new takes on Morris Fuller Benton's News Gothic and related designs produced for ATF in the period before 1910. There are 26 fonts, so there would be more variety, but not much noticeable difference in appearance to the average reader (I don't mean the font fanatics you find at this Board).

If you are truly looking for something to set you apart from Trade Gothic, which is itself a near-copy of News Gothic, it seems you might want to consider something different from either of them.

There are too many fonts being designed to keep relying on the same designs with new names and more weights.

What are the features that Trade Gothic has that you like so much? The 2-storey g? The simple monotone weight? The machined, precise look? The x-height? The mostly-closed C? Do you want a 'transparent' typeface? These are all questions to answer in your own mind and then start looking at font families.

Some newer families you may want to look at:
Hoefler's Gotham.
House Industries Neutraface.
Terminal Design's ClearviewOne.
Storm's John Sans.
Or for something more different, Storm's Sebastian

These are only a few families. LucasFonts and FontFonts also have a range of sans serif designs.

Go explore them all and see what attracts you.

I was searching high and low for a different sort of gothic as well, and I'm very happy to have settled upon Aaux and Aaux Office. You can see it in use here. In addition to the weights there, Neil Summerour is either about to release or has just released black and poster weights as well as small caps/OSFs. One thing: if you do decide to purchase Aaux (this doesn't apply to Aaux Office), make sure you ask T26 for real quotes/apostrophes -- Neil had decided against it when he designed the face, but in my view it severely limits its application. When I asked, T26 was kind enough to supply me a version with angled quotes (Neil was completely fine with their doing so, by the way).

Very funny. I was just about to write up a post about Benton at Typographica.

There's the new Benton Sans from FB...