...

or "to be seen as a person who plays an important role in the company" ??

it is important that you come across as as someone who matters

seems to fit the bill

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Note added at 27 mins (2007-10-20 08:16:55 GMT)
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39 thousand or so google hits

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Note added at 30 mins (2007-10-20 08:20:00 GMT)
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For men, the Moko showed their rank, their status and their ferocity, or virility. ... could be identified as a person of authority, in charge of warriors. ...
yoso.wordpress.com/2007/07/26/origin-of-maori-tattoo-ta-moko/ - 30k - Im Cache - Ähnliche Seiten

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Note added at 31 mins (2007-10-20 08:20:40 GMT)
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Where an employee, manager or director is concerned that a violation of the code may exist, a designated person of authority and status will be made ...
www.naspers.co.za/English/codeethics.asp - 28k - Im Cache - Ähnliche Seiten

I'm not sure if this fits the tone of your text, but at least it sounds like English and probably fits with the actual ambitions of this sales rep. It's also gender-neutral without being too politically correct (i.e., you get away from the word "person").

Something along the lines of this:
"It is important for you to be seen as a major player and have/assume that status."

Another possibility - perhaps more in line with the register of your text: "someone people look up to and respect"

I also thought of "a mover and a shaker" (but that would perhaps be more suitable for someone in management - oder?)

Hope that helps.

It's interesting that most other Answerers intuitively and rigthly avoided the dictionary solution "meaningful/significant person" and sought alternatives. I (like Paul) also thought of "respected", but that's not the same thing here.
Perhaps the solution lies in using the word "figure"?

In the context of the sentence, 'major player' would fit the best imo. "(...) it is important to be seen as a major player (...)". Compare that to the longer options and you might find some redundancy. "(...) It is important to be seen as someone people look up to and respect" you get two words with the same meaning in this sentence twice (see/look, not to mention look up to and respect), and it messes up the flow. I think that if you want to go for that option, the sentence would have to be changed drastically into something like: "it is important to gain the respect of people", which gets rid of the redundancy and lack of flow, but also stops conveying the complete meaning of the German sentence.
Therefore, I think 'major player' is the best option.