If you are familiar with Eurorack format, most of the stuff is also mono. There are some stereo modules but not as many as mono. And one of the reasons for this could be that most sound sources are actually mono, not stereo, like oscillators, etc.
If you for example want a phaser to not only be in left side, you can simply just connect the output of the phaser to left and right output. It doesnt give you a stereo effect, but a dual mono effect. But in many cases this is good enough imo. I have plans to update a phaser I made for stereo version, but I think it will end up being a mono in > stereo out phaser.
Another reason, building everything in stereo also means you need 2 of every object = double DSP load.
Me personally, I usually never use like 3 stereo effects for a sound. I would probably use a mono drive stage a mono compressor and THEN to a stereo effect. Examples of course, could be any effect. This does save a great deal of DSP resources for other purposes.
So in general it is a good idea to do some testing and think if one actually needs 3-4 stereo effects in an effect chain or you can do with:
Mono Fx1 > mono Fx2 > mono Fx3 > and THEN a stereo effect to add some "stereo space" to the sound.
As technobear wrote using shift+ctrl give you finer resolution when dialing the parameters with the mouse.... But if you for example modulates the filter cut off with an envelope or an lfo the modulation is not steppy. So it also depends on how you do it.
If you for example use a midi controller for controlling the parameters of Axoloti, you aso only have a resolution of 128 steps. Which also cand sound a bit steppy.
About the stepping and suggestions to how to fix it:
A way to remove the steppyness, and this goes to both using mouse and using a midi controller with only 128 steps resolution, you can try to use the math/smooth object:
Connect the dial to the input of the smooth object and then connect it to for example the modulation input of a filter. This will smooth out the steppyness a lot. You can even set the time of how long it will take to get to the next value.
How to use the smoothing object:
If you are familiar with Acess Virus synth, then you will see a good example of what smoothing can do of positive things to a parameter smoothing. When you dial the parameters of the Virus very rapidly, you will see that the the actually movement of the knob you are dialing will be a bit delayed and kind of "glide" between the values. This is smoothing. And imo one of the reasons Virus synth sounds so smooth.
If you want to see opposite example of smoothing take any Waldorf synth. Their encoders are extremely skippy and opposite Virus most waldorf synths will litteraly JUMP from one value to another if you dial it too fast, like go from 10 to 126.. and then skip all the values inbetween, like extreme case of the steppyness you talk about.
TO avoid steppyness in another way, you can add your own potentiometers, which uses CV and will also have a lot higher resolution than just using a midi controller. This also prevent steppyness...
So there are a few things you can do now all ready to make the parameters sound more smooth.
Hope that helps a bit!