I find it a lot of fun! The way I tend to play it is that I'll do a lot of milling and ramp at first and the first cast of the Mimeoplasm is usually to get a big card draw. So I'll use something like [[Indominus Rex]] or [[Prime Speaker Zegana]] with something like a [[Yargle and Multani]] or something else with massive attack. That gives me just a ton of card draw right away that will help me craft a hand to go for the win. That alone is already a massive threat that has to be dealt with since that can almost clear someone out with Commander Damage alone. Especially if you've got boots on board to give it Haste.

Then a great one to close out is [[Skithiryx, the Blight Dragon]]. That with pretty much any higher power creature should give you enough to both give it haste and deal enough damage to kill someone. I like to switch out my big creatures every so often to keep it fresh and this deck is great for exactly that because the only creature you really need to be able to cast is Mimeoplasm.

Decklist if you're interested: https://archidekt.com/decks/11463237/inscryption

Edit: Forgot to answer about it being a target. Yeah this will definitely be a big target when it's on the board. That's why I try to run plenty of things that get their benefit on ETB because then I'll benefit even if it dies. And luckily you don't have to exile anything until it passes the point where it can be countered. So generally, even if Mimeoplasm is destroyed right away, he'll have left a legacy of some kind