Unlocking first tech of the next era triggers entering that era including fireworks and some bonuses and such.
Several GBs (ToB, LoA, SMB, FoD, RAH, RFP, AM; some better than others) also produce goods which from Modern Era onward are unrefined goods from 3 ages back that must be consumed to create the current age's goods. Those GBs do make it easier to advance tech/map without trading or taking up precious city space with those old goods buildings. And if you're avoiding fights then you'll need quite a lot of goods to negotiate in the campaign map to unlock the only way to obtain mars ore and asteroid ice later on. That's a point I got stuck on when advancing to space ages, my campaign map was pretty far behind and it blocked my tech tree advancement until I could slowly scout my way through the campaign map (it's super slow - 31 hours per province in SAAB!).
Thanks Beelz it's a pleasure to be part of the team and I look forward to continuing to help and share knowledge about this wonderful community!
I found that there are two versions of the tutorial as well, one that is longer the very first time and after that it's a bit shorter but still there every time.
Here are the details: https://forgeofempires.fandom.com/wiki/Tutorial
Yeah foe.tools is a nice website. Also I found a similar set of tools before at https://www.foetools.net/gbleveler.html. Very similar name!
Thanks @Beelz it's an pleasure to join the admin team and continue building up our wonderful FoE wiki community.
I think cape is definitely worth it, getting to level 30 is a bit of long haul but then 30-70 is easier with the profitable contributor slots.