Hey eMD,
First of all, there are two types of main reverbs; Convolution and Algorithmic. Convolution Reverbs - in this case, I assume you use VSTs to achieve reverberation - use real sound samples, recorded from live environments, known as "Impulse Responses". Since they use real sound samples, they create more "realistic tail" and feeling of reverb. Effect process of convolution reverbs basically mix your signal with filtered signals that you want to achieve. So you can think that for one sound, you basically process two sounds. Therefore, it has a huge impact on your CPU as well as your DAWs performance.
As you can guess from the name, Algorithmic Reverbs create paramaters to mock "realistic tail" to generate reverbration. All of DAWs come from one or more algorithmic reverbs. In my opinion, algorithmic reverbs sound okay when you apply on ambiance sounds, FX etc. If you apply on solo instruments or real instruments, it does not give that realistic feeling.
I'd recommend you to use convolution reverb on synths, snares etc. where you can use algorithmic reverbs to give little bit more space to additional/extra sounds on your track.
If you're an Ableton user, they do great job with their custom reverbs. If you'd like to use another VST for reverb, you can try Arts Acoustic for algorithmic reverb (I am sure that lot of producer friends in this forum use it) and Liquid Sonics Reverbrate for convolution.
Personally, I only have maximum 4 reverb (two algorithmic, two convolution) bus track to achieve reverbration in my tracks. That way, I minimize CPU usage and do not create muddy, non-realistic mix.
Thanks for the response! I was wondering where Valhalla Vintage Verb falls in this?
I do use Ableton, my follow up question would be do most people use reverb on returns or on buses? I find I have more control when using buses. What are some pros and cons?
Using a bus consumes less cpu and makes it so your soundscape doesn't have a million different reverbs.
I can't think of any cons for using buses, it's more just preference. Sometimes, I use. Sometimes, I don't. It depends on the sound I'm going for really.