Boba Fett is nowhere near as close to my heart as the Joker, so that's not an argument.
As a kid I loved Boba Fett, mostly because of the toyetic visual of him. His death in ROTJ was one of the biggest disappointments for me though and just one of the many reasons I think ROTJ is weak. But I was never enamored by the character like I was with Vader, Luke, Han, etc. In fact, it wasn't until around Attack of the Clones and the internet that I learned that there was such a following for him. He's overhyped and overrated.
Yeah, yeah, and keep going on about the voice. I grew out of that. In the mid-90s I made a homemade Halloween costume of Boba Fett with a little sewing kit recorder that I placed in the right breast plate where his logo was. I recorded his lines of dialogue on the recorder from the VHS "one last time" set so I could press it the right side of my chest and "speak" those lines. "He's no good to me dead" was my favorite line. When I bought the OT DVD set, nobody hated the change more than me. Then when toy companies started putting Jango's mug underneath all the Boba figures, I was pissed. That was 13 years ago though. If I want to hear the original voice, I can make a YouTube tab right now and hear it and relive my childhood memories of finding his figure at a flea market or paying out the ass for the POTF2 "circle glove" variant of him.
Boba Fett isn't that great though, even without Jango. He has a few cool moments in Empire and that's it. Being a clone is the best thing that happened to him when you compare how he was handled in Return of the Jedi and all the lame Expanded universe crap he was in. Even his very first appearance as a cartoon is utter ****.

I once thought as you do "should have just made Jango, Boba in AOTC", but 1. Boba would still suck by the end of ROTJ and 2. technically Boba Fett is Jango Fett. It's the same dude.
The ideas and adventures I had for the character as a kid were way better than anything anyone else has come up with for him on film or page. I don't think Lucas slaughtered some sacred cow by making Boba Fett a clone of a bounty hunter named Jango Fett. That character was already ruined when he was hanging out at Jabba's palace for no reason and fell into a killer vag in the middle of the desert. If anything, the clone thing is an improvement and Jango is an arguably cooler name (along with the cooler dual wielding pistols). For you see, Boba Fett was never about substance, only style. He alerts the Empire about Han, gets to take him to Jabba the Hutt, and that's about it. That's where his "character" ends. Jango has and does more. Is working with the bounty hunter chick and poison slugs thing stupid? Oh yeah, it's bad. But taking multiple Jedi head on (and winning or breaking even in each encounter), fighting aliens beasts and having the closest thing to immortality and a legacy through an army and "son" that look just like you is arguably cooler.
I'll always prefer Boba for nostalgia reasons and even disregard Jango, but let's not kid ourselves. Boba Fett isn't any better of a character. Nothing about him was "ruined", unless you're still 8.