Brooks I grew up in Eugene, right next to Springfield. That area is still one of my favorite areas you've got the Cascades to one side, the Oregon Coast to the other and great sites south... up north you have Portland... well 3 out of 4 isn't bad LOL. But seriously it's nice around Portland too.
As far as staying in Eugene-Springfield. I've only stayed at one. That's the
Eugene Kamping World which used to be a KOA - its a bit north but not far at all and just off of I-5. It's not amazing but decent and number of full time rigs along the sides that we say during our couple of stays. You also have
Premier RV Resorts on the other side of I-5 both of these are in Coburg. Premier is pretty large with amenities, but I've never stayed there.
Deerwood RV Park is south of Springfield. From the photos it looks a bit nicer, and without the heavier traffic you'll find from the two up north along I-5.
Bit further out is
Dexter Shores RV Park never been there but I have been up on the lake. Bit more of a drive but will give you better views and a slower pace of life.
Good luck.
