Installing modifications on Battle Smith’s Steel Defender (5e)

I’m currently playing an artificer in a homebrew campaign and looking at the SD’s stat block, as well as other people’s opinions, it’s pretty much just a tank with its damage being negligible at best, so I was wondering if there are any balanced homebrew rules someone has made to install modifications on the SD, because that just seems to be the natural thing to do for a class called the Battle Smith. I’m not talking about putting infusions or magic items on the SD, but adding/swapping on its abilities and stats.

Of course my aim isn’t to make it OP, but more on to customize how I want it to be as well as make it scale better. I could just talk this out with my DM but I don’t want to have her make an entire ruleset on Steel Defender modification from scratch.