keep in mind my experience of source is with and from the perspective of level design, not programming.
short answer:
depends on what you like in an engine.
really though look at this shit. proper, actual level design tools rule

keep in mind my experience of source is with and from the perspective of level design, not programming.
short answer:
depends on what you like in an engine.
really though look at this shit. proper, actual level design tools rule
the lack of good LD tools in modern engines is an absolute travesty, i miss using Hammer so much despite all the problems with the stock 2013 branch one
praying every day for a source 2 SDK (or better, permissive licensing for the whole engine now that Havok is gone)
legit. level design is so overlooked now that all the tooling is gone. eg blizzard trying to balance layout issues with gameplay changes in overwatch. attack/defend isn't a bad gamemode, you just had awful chokes and no one wants to edit the intricately artpassed level mesh in fuckin blender.
don't get me started on the code wizardry that the Titanfall 2 community managed to do to a modified version of the Source Engine that is used for the game. we all thought Community servers were just Not Possible until some code mages pulled the game apart, went "hmmm, since it works similiarly to Source, what if we did X Y and Z" and proceeded to slowly bang out Northstar.
sure, i'm pretty sure community maps are like, limited to map edits atm, but the fact they managed to slowly make Community Servers when Titanfall 2 was unplayable, GET ATTRITION AI WORKING ON SAID SERVERS, and pioneer the resurrection of the funny high speed pilots vs giant fucking robots game that is Titanfall 2 before the "Janitor at Respawn" finally fixed the issue themselves is a testament to how weirdly usable Source Engine still is.
we know someone who was at some point involved in reverse engineering titanfall 2's BSP version, actually! apparently there's a lot of weird stuff done to it, and a /lot/ less leftover VMF info to decompile with. for more 'standard' source games, pretty much the only things you can't properly recover are area portals and displacement base brushes.
unironically explains a lot as to why progress on community maps was slow. like, again, i'm vividly aware TF|2 was running on a highly modified fork of the engine, but the fact even the map files are that different explains how long it took to get the AI functional, beyond just "Stryder holding some of the files on it's backend and having to try to faithfully remake them by hand"
for sure. from what i remember it looked like respawn went ahead and just made props bake directly to world geo in the same way as brushes do, so it's really hard (not possible?) to separate them back out for editing.
This isn't all props fortunately!
Unfortunately they are a real pain to decompile
No model paths or angles are stored, just the geo
Interestingly, it's very similar to Quake III "triangle soups"
I'm the main R2Northstar maps guy!
We're slowly getting closer to decent quality maps
For now tho we want to keep the tools less public
Using the tools is super painful rn
(And I don't wanna field support tickets)
Working out navmeshes was a cool exercise tho
I should look at sharing it's history in a blog or something...