Perhaps, sure i'll give it a look, my idea was to make it nicely geometrical, and really remove tedium, as we went straight from 750 to 1250, a nice 1000 gap felt much better
ofc, i could have also added back the 1250 of base advciv, but it didnt seem to provide extra value vs 1000 so i thought better support 1500 rather.
Another factor is our tech tree is fairly thin on design (i.e. we don't have that much techs), and i removed +/- 10 techs to the future era, so making marathon lighter may have helped comrpess history a bit, even if these techs were at the end of the tree anyway, i needed early eras to end a bit faster too (and generally i wanted to cure the issue of late industrial+ being super tedious).
If you find it valuable, i may add a 1250 timeline as in base advciv, we have the room, i just though 1000 vs 1250 is aboutthe same, and someone wanting 1000 woudlr ather straight go to 1500 maybe.
A note though i dont remember very well but there were some values that may have been asymetrical in base advciv (like goign from 4 to 12 or 9 instead of 4x 2 = 8, 4 x3 = 12, 4x4 = 16, as i liek to do in advciv-sas generally

) (i.e. mathematical gradual even spread, especially for handicap xml values btw although not directly related to this)
i believe these may be easier to take a look into after i make the gamespeed chart, which i am doing atm with GPT-5.2-Codex and chatgpt 5.2 (web) to continue there xd, mirroring the new handicap chart. It allowed me to spot a last human field i had overlooked to put to 100 always for huamn and adjust bit for AI too (GPThreshold, about great person something)
otherwise glad to know 48 civs DLL is working great, from autoplay runs i tried, generally before a new release xd to eb fair, A is super competitive in it and doesnt die easily, so games seem close at least on samples i played which looks intense and possibly super fun xd
then after gamespeeds are cleanly settled, i'll most likely make a new maps chart as well mirorrign same pattern (not promised nor guaranteed, but as things are going it may be a nice continuation

)
then we can review XXL or even XXS for that matter xd i wouldnt mind!
edit: if you have mods or links for small maps please send them too, i'll consider them for review as well!
edit 2: just to be sur ei got it right, by standard values, do you mean the BTS ones? From what i remember, they were 1500 turns at 300% no? I'd need to recheck to be sure as it may slightly be different, but i believe our slow speed matches that if it was that.
Btw i already have a working draft atm for the gamespeed chart, based on the handicap chart, so need to polish it now, thanks a lot GPT-5.2-Codex and then i assume chatgpt 5.2 web or such forpolsih thanks
