I'll ballpark you some numbers here...
Assuming you make 80K and the ex 40K, 1 child and in Ontario, w/ 50-50 access...meaning offset CS
You'd pay the ex $364 month for CS or 4368/year. (your CS (724) less STBX CS (360) )
as per
CS Online Calculator
Your net = 64450 (approx.) (80000 less 14550 in taxes)
STBX Net = 34000 (approx.) (40000 less 6000 in taxes)
approx. values as per
CRA Income Tax tables
Total combined income = 98450 (your net + ex's net)
YOUR TOTAL = Net - CS (61082)
STBX TOTAL = Net + CS (38368)
CURRENT Net Disposable Income:
You: 62% of total
STBX: 38% of total
The SSAG guidelines WITH children would indicate your ex should be between 41 and 46% NDI.
41% of 98450 = 40374.50
46% of 98450 = 45287.00
40374.50 - 38368 = 1996.5 / 12 = 166.37 /month (low range)
45287.00 - 38368 = 6919 /12 = 576.58 /month (high range)
She's very very close to the min. range of not even meeting the financial aspect of entitlement. Like sub 2K/year.
But if you look at the figures here, you can at least get a rough idea of what you are in for. My numbers are fairly close to what you are getting out of My Support calculator, so they look to be at least in the right direction. My info doesn't account for the included income tax breaks/etc either, which may account for the slight variations.
You would have an argument against spousal, considering she is sub 2000 away from the low end of entitlement.
Personally I would offer her low end, with minimal duration (with a FIRM termination date) and settle for mid range (mid 300's), w/ minimum duration.
I wouldn't do 9 years...I would stick firm to 4.5 at most.