No, unlike SMW, even if you're maybe a pro, it still takes a long time to edit SMRPG. There's no easy way of inserting custom music or anything like that, but if you were an expert programmer that's different, depending on how you're good.
Probably not completely, but only slightly. I worked on a SMRPG hack for sometime, I have no plans on working on it though. I thought it was pretty good, but I'm far too busy.
I recently found one called "Super Mario RPG Revolution". I don't know if I can tell you where it was at, because I got it as a ROM instead of an IPS. (Incredibly enough, the file that had the unaltered ROM wasn't working, but this one did!)
The story and level layouts are unchanged, but the initial Bowser battle was edited to where you have to "defeat" Bowser before being allowed to attack the chain. (hit him until he become invincible). Just about all the enemies have had their stats upgraded or new attacks added, and every single boss has been completely rescripted to be a brand new battle.
For example, the first boss fight in the game, the Hammer Bros. Instead of fighting two, you fight one (since there was only one in the actual level, not two). He has upgraded stats, and a new attack where he spazzes out, then throws a single hammer for massive damage. I couldn't even beat him until I hit LV 3. (I got pwned by a Goomba at LV 1, embarrassingly enough!)
To further increase the challenge, some of your allies' attacks have been changed around as well. I have only gotten to Moleville so far, but Mallow never got Thunderbolt, starting instead with a severely nerfed Shocker. Mack's invasion was incredibly tough without a single multi-target attack!
Croco's second fight, rather than steal your items midway through, instead had higher stats as well as summoning Microbombs like the first part of the Punchinello fight.
Finally, all allies start with special equipment. Mallow started with a Froggiebelt to slightly boost his ATK, and Geno had a Toy Cape as armor. Some items have been upgraded in effect as well as price, so spamming Pick-Me-Ups are an incredibly expensive strategy. I've been reduced to save-scumming at Yo'ster Isle to get Yoshi Cookies, then using those to afford decent items, as well as the regenerating treasure at Rose Way to afford equipment!
EDIT: Sorry, I just realized I accidentally 2-year-bumped a topic. On the bright side, at least it was a decent, informative post. I don't think anybody here's played it. I'll try not to do this again, sorry.
-------------------- Current Projects: "Legend of Zelda: Balance of Power" (A Zelda Classic quest)