The tuxedo is a timeless and classic style that is the exact opposite of "tacky". The tuxedo has been donned from the likes of Heads of State to rockstars and from Frank Sinatra to Jay-Z. As previously posted its hard for a gentleman to look bad or go wrong with a well made and well fitted tuxedo. The tuxedo is and of itself proper evening wear and quite frankly, cool.
A properly dressed gentleman does not need to make a special effort to "stand out". In fact, the role of a gentleman is to be the silhouette for his accompanying date. The one who should be receiving the attention and standing out should be the young lady on your arm. She has put a lot of time and effort to look beautiful and elegant for you. She certainly does not want to compete with her own date for admiring eyes and attention. It's your job to make her feel and look sexy and if done correctly could lead to a handsome reward later in the evening.
The problem may arise if one needs to rent a tuxedo. Although it's preferable to own a tuxedo there is nothing wrong with renting. Especially for a young man in his high school years who is still growing and/or may not have it within the budget to purchase. Many rental shops just want to get you out the door with an ill fitting suit in order to collect there fees and have little regard for your personal style or fit.
With that said it would be my advise to spend the time visiting the various rental shops in your area and try on different models until you have the proper fit and style. By proper fit I mean slacks that are hemmed to your size and a jacket that fits snug yet comfortable and proper shoes. If a well fitted tuxedo is the epitome of a gentleman's evening wear, an ill fitted tux will have the opposite effect and indeed could be considered "tacky". I've added a link below to show some examples of how great a well fitted tux looks on different personalities.
Thank you for including a photo of you and your date from last years event. You both look great and it appears you have a strong sense of personal style and that you take pride in your appearance. With that said please accept some criticism with the best of intentions. I'm assuming the event last year was in the evening. If so, the sport coat and slacks you are wearing are neither formal nor evening attire. A gentleman should always wear a dark suit and tie for formal evening dress and if specified black-tie then a tuxedo (a white tuxedo could be used in summer months). Secondly, your slacks are way too long. If you care about your appearance, and I'm assuming you do since your on this website, you need to have your slacks hemmed in order to fit properly. Slacks that are too long appear sloppy. The same goes for your jacket. It's a little too big. You need to have the sleeves shortened and the jacket altered by a good taylor. As mentioned above you want the jacket to be snug yet comfortable. And as for the shirt, again a little too big. You could of used a shirt one size smaller. In my opinion, with these small suggestions you would of had a smarter more taylor made look. Again, you both looked great so please accept my opinion as that. An opinion.
Good luck and let us know how things turn out.
Here's the link I mentioned: