most decent effects depend upon weird engine-specific edge cases. Some of seven's effects also seem to be heavily framerate dependant, and can drop framerates from 2000 to 300 just on their own (less noticable at low framerates, so its okay if you've got rtlights enabled).
I know this from trying to convert seven's effects to fte's custom particle system.
dp's effectinfo stuff is still pretty hardcoded, all you can really do is specify randomized colours+origins+velocities. Basically what I'm saying is 'make a tracer with it'. Also, 'type smoke' is rather ambiguous, and the sort of legacy behaviour that you're probably best without.
Its generally not practical to reimplement, without copy+pastaing the entire gl_rpart.c file or whatever it is.
There's also the fact that it doesn't work with QW-style content downloads, where the mod and all of its content is automatically downloaded from a server file-by-file (as far as I'm aware, dp also has this limitation), while (more vanilla) modified nq clients still only support maps. This limits the use to only single-player mods/content packages.
The network protocol LH added for spawning custom effects from ssqc is also flawed, limiting its reliability and thus usefulness (its based upon csqc, so uses client-specific indexes in the server, which is vile when you consider custom content packages - it should have used precaches).
Also, I like curly brackets too.

They help break up the words and give it structure, instead of it just being a huge great splurge. Makes it so much easier to find the effect you're looking for as you can look directly at the names instead of having to first figure out if it is a name.
No system is perfect, but its at least a step in the right direction.
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