

Oh yeah definitely, game systems are rarely a good implementation outside of the combat. Many DnD games are definitely good (I’ve played neverwinter nights series, baldur’s gate series, dungeons and dragons online), but the real charm in DnD is playing with your friends and having a good time (as well as hyperoptimising your character at the same time, if you like that) (honestly I believe that’s one of the realisations WotC made with 3.5e that led them to make 4e, and subsequently 5e, a lot simpler: making it easier to get your friends into it was more important than having myriads of options for breaking the game)
Yeah but those are different niches. The people that already played 3/3.5 didn’t feel like 4e was for them (and in a way, it wasn’t), so they moved on to pathfinder etc. Some newer players got into dnd with 4e but it alienated the older minmaxer types that liked 3(.5)e. (I have not done any research and this is all gut feeling and 2nd hand accounts by the way). In 5e they struck the right balance to get a kind of 3.5e “light”, that can attract new players as well as satisfy older players, though of course you can’t ever satisfy everyone.
You’re right of course that mirror image and invisibility are super strong spells that don’t benefit from a higher save DC, but the pattern series of spells (of which I consider colour spray the single target version) are still super good.
In the end, don’t forget that “fun” is different for everyone, and with experience you might find yourself wanting to challenge yourself with “suboptimal” choices because it’s more fun to play your first gnome paladin than the tenth halfling rogue.