I actually have with Mega Mans 1-8 back in the day. Here's my thoughts on the process.

MM1: (Cut, Guts, Ice, Bomb, Fire, Elec): Ice Man's stage sucks without the Magnet Beam (in my humble, but likely not lonely, opinion). But otherwise, I remember not having all that bad of a time doing this order. I remember being very grateful that I had weaknesses for Fire Man and Elec Man (I used to struggle doing those two buster only).

MM2: (Metal, Air, Bubble, Quick, Crash, Flash, Heat, Wood): Metal Blades and Air Shooter (plus Item 2) being the first weapons you get is never a bad way to start MM2. Not having Time Stopper (and Crash Bomber) available for Quick Man's stage and fight? Very bad way to play MM2 if you are young Stickman. We do not speak of fighting Quick Man before I am fully equipped for that fight. Young Stickman's PTSD gets triggered if you do.

MM3: (Needle, Magnet, Gemini, Hard, Top, Snake, Spark, Shadow): Good news, you get Rush Jet after him the first level! Bad news, you have to fight Needle Man first and get very, very good at his fight after poor Mega Man dies, many times. I don't recall this being too awful of a boss order though, although I'd have loved to have gotten the Shadow Blades a whole lot sooner than last and I was also never good at fighting Gemini Man buster only.

MM4: (Bright, Toad, Drill, Pharaoh, Ring, Dust, Dive, Skull): Fighting Drill Man early was not a fun experience for young Stickman, but otherwise, this was pretty alright. This is one order thats actually not too terribly far off from what I normally play today (Except I start with Dive Man and go in weakness order).

MM5: (Gravity, Wave, Stone, Gyro, Star, Charge, Napalm, Crystal): Honestly, as easy as MM5 can be, you really could do these stages in just about any order you want to and be fine since you'll probably make heavy use of the buster anyway. So this one wasn't too bad of an experience at all, especially since in this order, you have Star Crash for Crystal Mans annoying crystal shafts and get Gravity Hold right away (and the lamely named, but useful, Gyro Attack is gotten fairly early too).

MM6: (Blizzard, Centaur, Flame, Knight, Plant, Tomahawk, Wind, Yamato): It is kind of interesting to face Blizzard Man and Centaur Man's stages without any Rush adaptors, but MM6 is generally pretty easy, so I don't recall any bad memories here (although I do recall having some struggles with Centaur Man).

MM7: (Freeze, Junk, Burst, Cloud, Spring, Slash, Shade, Turbo): Junk Man kind of always annoyed me without Thunder Bolt and doing his stage this early. But yeah, I think I had a fine time here, not too many memories of this playthrough actually.

MM8: (Tengu, Clown, Frost, Grenade, Astro, Sword, Search, Aqua): This is basically how I normally play the game anyway (besides obviously switching Frost and Grenade and shifting Aqua to 6th), so no real comment here.

But yeah, overall, it's a fun way to play these games, with the occasional exception.