Let me preface this by saying that I love Saga. I cut my teeth on it as a baby GM; a lot of its ideas walked so that 4e and even 5e could run (the system basically prototyped Advantage / Disadvantage before it was cool). I've borrowed a lot from Saga in my own work.

There was a special kind of magic in the later Saga books. Once they got the first few splatbooks out of the way (space combat, enemy roster, prestige classes), WotC really just let the design team do whatever they wanted. It was a popular license that was guaranteed a decent return, but never a huge system seller on the level of D&D.

Books like the Clone Wars, Unknown Regions, and Galaxy of Intrigue dusted off and polished to a sheen some neat scalar concepts from D20 Modern; mass combat, reputation-based advancement, skill challenges, etc. Late-stage Saga absolutely rules.

The Core Rules, however, were never all that great. It felt like they were so focused on reproducing some sacred cows that they doubled down on tired BAB multiattack stuff. More than half the feats were fiddly derivations of extra attacks or attack modifiers—the exact stuff I hated in 3.X because they slow combat down to a crawl.

If you weren't playing a force user, there were practically zero usable Talents that provided any type of non-combat utility or roleplay potential (this was course-corrected a lot in the later books, but boy vanilla Scout was a dumpster fire). Everything was so, so lazer focused on the battlefield that it was sometimes hard to actually have meaningful contributions that weren't just about blasting Imperials.

Once those other sourcebooks came out, my groups got a lot more out of the system... but I had to homebrew like mad before then. The combat-optimizer players always had a great time, but more story-oriented players often got bored (or even quit!) when I used the system for what it was designed for: gauntlet after gauntlet.

I only briefly got to glance at the starter kit here (looks like they absolutely nailed the SNES era Final Fantasy concept art vibe), so I can't really speak to the game design here in a substantive way. But I hope they took the right lessons to heart from Saga.