If you have severe problems with speaking, is it okay to use more text and equations on slides?
Slides with a lot of text or equations aiming to be self-explanatory tend to:


visually overwhelm the audience and don’t provide visual guidance – which is more relevant in talks than in written text as the audience needs to multitask to some extent, listening to the speaker and reading the slides at the same time;
contain more information than the audience can digest in the given time – regardless of what the speaker does;
have overly small text and graphics;
be read verbatim (which usually is a bad idea).


Mind the tend to: Neither are these issues inevitable, nor are they tied to the slides being self-explanatory. Rather, they are what often happens if an inexperienced speaker tries to make slides self-explanatory. In fact, I would consider most of my own slides self-explanatory and I am rather confident that my talks do not suffer from the above problems.

Hence I think your strategy to make your slides self-explanatory is fine – if you avoid the above problems. In detail, I recommend:


Avoid complete sentences, as they are bad for discontinuous reading such as usually done in talks.
Make sure that the main structure of each slide is easy to grasp.
Find a reasonable trade-off between not putting too much information on one slide and showing slides long enough.
If possible, use some test audience to ensure that your slides can be comprehended within the allotted time.
If a slide is complicated, build it up step by step in pieces that can be assessed by the audience within seconds.
Be careful not to overuse this feature, e.g., by uncovering a list item by item.
The audience likes to read ahead, in particular if you are rhetorically challenged.
Self-explanatory does not mean containing all the details.
In most cases, you barely have sufficient time to communicate your main message – only show what is essential to this message or at least make sure that sidenotes are visually distinct.
For example, if there is a standard way to choose the temperature at which you conduct your experiment, you usually don’t need to write this on your slide.
If you know that there are some people who cannot stop themselves from asking about this or it may be interesting for some members of the audience, give this information on the slides in a smaller font size or visually separate (and don’t talk about it).