I'm currently using a dated version of Sony Movie Studio Platinum 12, which is easy to use and gets the job done, but I'm considering an upgrade.
 
Main application lately was mostly combining various videos captured during live gigs (align to audio recordings, cut, edit, zoom, adjust light, simple FX) so nothing terribly fancy.  Image stabilization I did not have but that would have been nice ...
 
One upgrade path would be towards VEGAS PRO 14 (but which version?). Other options?

Currently bundle of vegas pro and dvd architect is 200e on steam
http://store.steampowered..._Pro_14_Steam_Edition/

I got vegas pro when it was on sale.  Great bit of software that will do whatever I need.  I don't know if Majix updated the studio version of Vegas or sale their own cheaper software instead.   The Vegas studio is the same except for more effects, mostly.

The familiarity with what you own makes upgrading to Vegas Pro the easiest transition.  I believe pro versions from pro 12 on have some form of stabilization.  The other upside of upgrading to the pro version is that if you are unsatisfied with built-in stabilizer, you can try various third party option plugins. I use the Adobe suite.  I hate their variety of subscription model with a passion, but can say the products work well.  They are probably overkill for what you are trying to do.
 
Another option to consider is the free version of Black Magic's Da Vinci Resolve.  The upside is it is free and very powerful.  It also has better color correction options than either Vegas or Adobe .  It too has image stabilization.  The downside is that most third party plugins do not work with free version (doesn't sound like you will need them) and the learning curve is harder than Vegas.  Stiill, considering it is freee, it may be worth your while to check it out.

Rob
In April Magix were running an upgrade offer for $49 - I've copied it below.
Why not contact them and see if they are still running with this?
Nigel
 
Hi Nigel,
Good news – we've extended the offer!
 
Update VEGAS Movie Studio 14 now and save.
 
Version 14 is sure to impress with new creative ideas, intuitive controls and innovative functions:
» More intuitive user interface
» 4K monitor support
» Impressive multicam editing
» Enhanced trimmer window with Hover Scrub technology
» New Vignette effect
» Optimized RAM previews
» Direct upload to Vimeo, YouTube and Facebook
» Plus: Music Maker ($59.99 value)
 
Available exclusively in the VEGAS Movie Studio Suite:
» VEGAS Movie Studio Platinum
+ effects, titles and transitions from NewBlueFX
+ built-in soundtracks with Sonicfire® Pro 6 from SmartSound®
+ HitFilm Toolkit Pack ($129.99 value)
 
 
Experience a new era in video editing with VEGAS Movie Studio 14 Platinum. Create. Simply.
 
Don't miss out: Order your copy of the latest version today at this exclusive Spring price!
 
Orders made before April 19, 2017 will receive Vasco da Gama 9 HD Essential travel route animation software as a free bonus.
 
For only $49.99 (regularly $179.98)
 

I bought Vegas Pro a while ago right before Magix bought it. If I had to do it again, I would have bought DaVinci Resolve instead. Black Magic has been very solid in their desire to make Resolve a possible front runner in the video editing industry so it's getting regular updates and features. Magix on the other hand are doing what they do best: absolutely nothing while paying for loads of advertising to get more people to buy their product and not updating it.