Giving a cheap, full damage, durable (can bounce shots from mediums well enough and gets skirts) unit the ability to outrange every enemy unit in the game less an isu is a fucking awful idea.... You want renewed stug spam? Because that's how you get renewed stug spam...
I wonder what you are thinking here. Where it benefits? It will get same range as all tank-hunters while beeing immobile and having less pen. Simply the option to use it as kind of a PaK to be more immunte to arty.
Still needs 4 hits to be destroyed and will be easy to flank in mode. Can only turn slow and out of mode gets back 50 range. The only benefit: it will be more intelligent not to rush into it.
The 62,5 range is normal for not getting trolled, so it can shoot back if get hit.