Quilting features to have in a machine/Bernina question (related!)

Hi there!

Here's my situation: I've been sewing for a long time, but have just gotten into quilting. 

I have a Bernina Activa 210 and love it.  It's super basic, doesn't do anything fancy, but the performance is beyond awesome. 

My "backup" machine is a so-so machine you could buy from any big box store, with a ton of bells & whistles (that I never use)...a well-meaning family member thoughtfully and sweetly gave it to me as a gift about a year or two ago.  I use it only when I need a walking foot, because it came with one.  But the machine makes me crazy.  And even the walking foot on it does not do a great job.

Here are the options I'm considering:
1. Sell the backup machine (I could get between $100-$130 on ebay) and buy the walking foot (and maybe a quilting foot if I have enough left over) for my existing Bernina

2. Sell the backup machine and trade the bernina up to a more "quilt-friendly" machine...that's the part I'm unsure about. 

Basically, will my basic machine (the bernina) be good to go for quilting once I get a walking foot (& quilting foot) for it?  Or are there other features I need for quilting, and I'd do better to just upgrade? 

Does that make sense?  I hope so! 

I'm willing to look at other machine brands, but I do love my bernina so I'd rather stick with that if I can.  But my one friend has a Viking and it's a thing of beauty...so I'm open to all suggestions.