In Spanish we hyphenate more ften than in other languages as we can split by sillables, not by root or endings like in English. We regularly allow hyphenation on words of 6 or more charcaters, but in narrow text columns even allow it on 5 character words. I personally dislike it. I aplly the non-splitting options at the end of a paragraph (runts)columns, or pages InDesign offers.

I see no reason for changing your preferred numbers when uusing them with spanish text, instead of English or French.

Our texts go a little longer (15-20%) than the same English text.
I would strongly recommend reading of James Felici gem: Typography book. From there I grasped my settings that are half of the max. values of: 5% for letter spacing and 3% for horiz. scale. I favour opening instead of tightening in most cases and thus I would use -2/+3 and -1/+2, sometimes I will equal both. BUT please keep on mind the main factor is the number of characters that fit one line in the text frame, if it’s low you have to relax them, or be more strict when the number goes over e.g. 60 characters. Let’s the Paragraph composer play the show.
And the most debated values for Word Spacing, I have found than on regular text frames, about 160-180pt wide using e.g. Minion or even Myriad at 8.5-10 points I cut the Min. to 90% and Max. to 150%, I see good results when leaving the Paragraph Composer enough air to breathen.
Again my advice is to apply some values, duplicate the text frame and try different ones, print them and compare. Hear opinion from several kind of readers and then use the preferred settings for that kind of typeface/size and text frame width.

Enjoy

If you just wanted to scale a particular character you could do that manually or via a character style.

A couple things. This was sort of implied at the beginning, but for type newbies, the hyphenation stuff should really be decided based on the column width and type size/style. Some clients or designers might always have a no-hyphen style, in which case for those that never change it, you might need to some day. Some client projects have lots of jargony long words that almost require hyphenation and then I try to avoid narrow columns. Sometimes I can’t though, so I change the settings. Just fyi about why you might want to change setting for those that don’t.

But I have 2 questions. I never did understand how the Justifcation Min/Des/Max word and letter spacing affected non-justified text. I wasn’t sure I understood the last line about headers. Can you elaborate?

Also, if by glyphs you just mean a subsituted character (which could be an odd symbol or else just a regular character but in a different font) why would you want to set an overall glyph scaling if it could be, say, an odd symbol (possibly too large) versus just a double caret (which might not warrant scaling)? I’m worried I’m missing out on something.

And yes, that bleeping tucked up runt behaviour bugs the heck outta me.

But why ID would put the runt on its own line one moment and back up on the previous line the next moment is a mystery. I’ve seen ID do this kind of thing, too, and it’s kind of weird. The rules of when that last word gets pushed up seem to change depending on InDesign’s mood.

In other words, they were about to waste valuable white space at the expense of avoiding orphans, widows, and abandoned subheads. That’s when their copy editors pull out their hacking or padding tool to make the story work