So yeah, I like the Gen 1 cards but there was a lot wrong with the game.
1. Horribly unbalanced. The game was so unbalanced the best strategy was going with mid HP, low Attack mons and cycling your deck to get anything you want. You want an example, try the TCG for Gameboy. It's stupid easy to win once you have enough cards to do the Haymaker. Other archetypes like Energy Tans and Rainmaker really just weren't as successful.
2. For whatever reason the Gym series is almost entirely illustrated by Ken Sugimori, and it feels strange, honestly. On the one hand we got some new art that wasn't seen anywhere else, but on the other hand could you imagine if we'd gotten some badass later artists like Miki Tanaka, Tomokazu Komiya, or other extant artists like Tomoaki Imakuni had been doing card art for the set? I don't think it was a money thing either; I think they were afraid of diverging from the established style, a sin they'd come to repeat later on.
3. The US was often plagued by supply shortages. I recall specifically we never got first edition products for: Base Set, Fossil, Gym Heroes, Neo Discovery, Neo Revelation, or Neo Destiny where I lived. Yet, probably 70% of my Team Rocket cards are First Edition. I guess I got lucky that's a good set.
4. Official products were... lacking. Theme decks were 40% energy cards, you got one rare. I think that was mostly just WotC. Though i think they could have made some better products if they had a longer leash.
That said I loved the cosmo galaxy foil, miss it, wish they'd use it again. Loved the large Yellow borders, the spiky evolution boxes, and the aesthetic.