Monitors are always hard to pick because none are perfect, and all have good and bad points. Add in the fact that everyone has different needs and tastes and you will never have agreement. For $400 you choices are limited and you can't get accurate colors, but I like my Dell u2412m which is around $300.
For serious gamers (young enough to be able to notice) lag obviously matters, but for most people they will not even know the difference.
I always say go IPS if you can, but the only thing that matters is what you like. I would never buy a TN monitor or a 16x9 monitor, but that is just me and I am old so lag doesn't make any difference. So you can ignore a lot of what is said and reviewed with regard to monitors when you take into account everyone is biased for their set of needs.
Also, as far a color goes, it is just personal preference unless you are actually doing color critical work. I have the NEC 3090wqxi with the spectraview software and calibration puck. This is a ridiculously good monitor with actually good colors. All other normally priced monitors don't compare to the color, but if you don't evaluate them side by side you would never know that your monitor's colors are wrong. If it is not your job to worry about color, then just be happy with your monitor if you like it.