Best entity to hold properties for high income earners

[George Xu]

My wife and I are fortunate to have steady, high-income producing jobs. Our rental real estate portfolio is also starting to produce a decent income. Our properties are currently held in pass-through LLCs which are not tax advantageous for us given our higher tax bracket. I'm thinking we should change ownership of the LLCs to a corporation, which will get taxed at a flat 21%. We don't plan on taking distributions and will re-invest the money earned in additional properties. 

Is forming an S-Corp to hold the LLCs the best approach given our situation? What are the alternative options? The things we care about in priority order are 1) Asset protection 2) Tax savings 3) Ease of maintaining.

Thank you!