I didn't see that as attacking FAGE, they were just pointing out something that was likely important to anyone considering systems.
I do agree that SotDL has better adventure support than AGE. (Schwalb is prolific.) Also in SotDL, characters gain a level by completing an adventure, which are broken up in different level-appropriate tiers: i.e., Starting, Novice, Expert, Master.
While SotDL does have a lot of mechanical options, it can almost be a bit overwhelming because a lot of it is scattered across various supplements. It's almost 3e levels of bloat. Thankfully there are fan-created spreadsheets for keeping track of the various ancestries, paths, and magic traditions. SotDL does consolidate a lot of this in later works. If you are interested in SotDL, I would recommend buying
Shadow of the Demon Lord,
Demon Lord's Companion 1 and
2, and
Occult Philosophy.
Again, the rollout for FAGE was far slower due to legal issues surrounding Wil Wheaton's
Titansgrave. There was supposed to be further adventures and a more comprehensive setting book for Titansgrave, but that died in the Legendary buy-out. In the mean time, GR published Blue Rose AGE - which has
a lot of adventure support - and Modern AGE. However, I suspect one issue that has limited GR's ability to provide adventure support - in contrast to SotDL - is that there is not presently a default setting, though I believe that the new Core Rulebook will present one in the same universe as their Free Port mini-setting.
AGE, as some people have said, is far more action hero oriented. My partner found FAGE easier and more fun to play than 5e D&D, because there was less moving parts for them to keep track of, but they still could make their limited selection of spells do cool things through rolling doubles and generating stunt points. AGE does have a lot of dials and knobs for dealing with some of its known problems (i.e., HP bloat), and I believe the upcoming Core Rulebook will also address some of it (within reason due to a desire for backwards compatibility). But my partner and I took part in the playtest last year, and the revised FAGE shows a lot of promise.
Have you looked at 5E? IMO, they addressed many spellcaster issues. For example, instead of a fireball automatically increasing damage based on the caster level, you need to spend a higher level spell slot to get more damage. This feature was then leveraged to good effect across many spells for all classes. (e.g., there's only one Cure Wounds spell... you just cure more damage by spending higher level slots.)
Thanks to a core concept of "bounded accuracy", things like bloated spell DCs were also reigned in.
Have you looked at either
Beyond the Wall and Other Adventures or
Through Sunken Lands? Neither game even has Fireball. These games present a much flatter power level between Cantrips, Spells, and Rituals. Cantrips and Spells don't have a spell level, though Rituals do based on character level (e.g., a level 2 ritual requires mage level 2+; a level 7 ritual requires a mage level 7+; etc.). Mages simply cast a number of spells per day equal to their level, and both games go to ten levels. Mages can still do amazing things, but the more powerful feats of magic power rest in Rituals, which require one hour per ritual level. Resurrection, for example, is a level 10 ritual; therefore, only mages of tenth level can cast it, and it takes ten hours to cast.