My voice sounds robotic after adding very few effects???

Well... let me give you one piece of advice about your setup that nobody seems to have told you - that the mic's in the wrong place, if that's what you are using as a script rest. The mic should be slightly above and beside your mouth line, not below it. Where it is now is pretty much guaranteed to pick up any extra voice clicks going. It's not quite so easy to tell from your picture, but it looks to me as though the pop screen is a little too close to the mic itself to work effectively - 3-4 inches is better. And for a comfortable read (and sound) you need to be 9-10 inches from the mic.

Speaking as an acoustician, I'd say that the treatment around your mic appears to be somewhat overdone, to say the very least. You need to analyse the reflective surfaces in the room that can feed back into the mic carefully, and just treat for those; the rest will have very little effect as far as the end result goes. Not all mics are susceptible in the same way to side lobe reflections, but since you haven't told us what the mic is, it's harder to comment further about that. But nevertheless, that looks like an excessive degree of treatment, which will have the effect of deadening the working space rather more than might be comfortable in a long session, and will be having very little effect upon the end result. There's a well-known saying amongst acousticians that says that 20% of the surface treatment does 80% of the work - and it's not wrong. Also, if those foam panels are mounted directly onto the wall, they won't be anywhere near as effective in the speech range as they would have been if they were mounted on battens 2 inches away from it. This is a common mistake that people make. As it is, they'll reduce very high frequency reflections, but won't do anything much for the mid range - where the speech band is. Doing a frequency analysis of your clean sample shows that there's a band between 200Hz and about 2kHz that is effectively untreated, and mounting the appropriate panels away from the wall would reduce that, which would result in a cleaner result anyway.

 If you are going to do long reads, then having a small table with a script rest on it tends to be a lot easier to use, although you have to treat the table surface to prevent an immediate reflection from it into the mic. But it's worth considering; we've found over the years that it means you can do more in a session without needing a break.

The whole point of optimising the speaking conditions is to minimise the amount of software corrective treatment you need to carry out, and over time, that can be a real time-saver. I think that there's quite a lot you could do to improve this situation, and that cumulatively it's likely to make quite an improvement.

What I can hear in this is a certain amount of sibilance, especially in the treated sample, and I suspect that most of your problems stem from the way you are recording - and possibly the mic you are using. If you don't get this right at source, then no amount of processing is going to make it better, and in fact it's likely to highlight the problems. It certainly will with sibilience, and the only effective cure for that is at source. So, what do you have as a recording setup? So that's the space you are in, distance from the mic, mic itself, pop screen, the lot - it can all make a difference.