"I am a young professional making between $150-200k annually. I've only been working a year, but have already saved close to half my yearly salary. I want to start putting that money into some sort of investment account, but I've heard that 401ks may no longer be a very good investment choice, so I am trying to decide what type of investment I should get into."
Congratulations on your early success! I wanted to address the comment you made that you heard that 401k's may no longer be a good investment choice. 401k's themselves offer the benefit of being able to defer taxes and potentially earn an employer match in addition to your own contributions. 401k's themselves are NOT investments. They are terrific accounts for delaying paying taxes and allow you to earn more growth on money that you should have had to pay in taxes. With the amount of money you are earning and saving, you should strongly consider using a 401k to shelter up to $18,000 per year. Of course, this money should be set aside and used to fund your retirement and not other future needs.
When you say, “401ks may no longer be a very good investment choice,” you may be referring to the fact that some 401k's are charging fees simply for having your money invested with them. I certainly agree that this is not in an investor's best interest and that this would weigh heavily on whether I choose or would recommend participation in a particular 401k. I do not know what percentage of 401k's are structured this way, but having participated in four different 401k's myself, none charged these outrageous fees. Bottom line--before ruling out participating in your company's 401k make sure you understand whether they are charging these fees or not.
Within 401k's, there are investment options usually in the form of mutual funds. These mutual funds are investments and some may be "good" and others "bad" investments. It is possible that a 401k does not have any "good" investments and that a particular 401k "may no longer be a good investment choice". Keep in mind that not every investment choice needs to be "good" you just need to have access to some that fit your investment strategy and most will have at least some attractive funds that you can work with. As long as there are some, you should contribute to your 401k and invest in those funds that fit your strategy.
You have done a great job of living well within your means and saving a significant amount of your income. You are already in a high tax bracket and are nearing the $200,000 limit that will impact how your investments are taxed as well. It is very important that you put together a strategy that leverages, 401k's and IRA's in conjunction with taxable accounts in a systematic way to achieve long term growth and reduce your current tax burden. The decisions you make can have a much more significant impact given your income levels than those that do not earn as much especially given the additional Medicare surtax that you may affect you.