This is quite technical but I think it worth mentioning. I tried a new version of Template:Coord based on Lua [1]. A heavy list with 230 monuments and coodinates now is served in 19 seconds instead for 25 sec. according with commented information included by MediaWiki in source pages. This time depends on many factors, but it is significant as I checked it on different pages just before and after updating the row template, and reduction time is quite constant. A list of 100 monuments is served in 4 seconds instead of 8 sec. Futhermore, it has reduced the number of expansion templates and the template inclusion limit now is higher allowing around 350 monuments.
[1] https://en.wikipedia.org/wiki/Module:Coordinates
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