I noticed that the tag system has a synonyms function, shouldn't we use it instead of naming tags like praying-davening-tefila?
I think that for non-English terms for which there's a concise English translation, it's valuable to have the primary tag in any synonym collection be a bilingual tag, to make it readily apparent to all users what the tag's about. Putting in a tag wiki summary that'll come ups as a tooltip helps with this, but isn't quite as user-friendly as just having the tag say what it is in English.
I agree that there's no longer any need for a single tag to include multiple synonyms or spellings in the same language.
This was caused because the original site was on the SE1.0 engine, as opposed to the current SE2.x engine, which did not have support for synonyms.
The problem is that this is a lot of work, and at this point its mainly the moderators that can create arbitrary synonyms (as opposed to the usual process, of having a well used tag marked and voted as a synonym).
I hope this will be done, in time...?