How many units you expect to be up at the same time? Maximum number of texttags allowed to be active at once is 100.
Generaly, you can speed up your triggers quite a bit by improving the general approach (e.g: instead of doing XXs if/then/else, just store colours in table and depending on mana/hp lvl, calculate the index and choose the correct tone with help of it) and reducing the number of invocations: store things like (Picked Unit), temporary values for further calulations (length of substrings) and usage of constants (e.g dummy string displaying length and form of generic bar).
However, 0,05 periodic loop with number of interations equal to number of units on the map is never a good idea. You could also benefit from usage of GUI Unit Indexer.