spouse visa financial summary query

Hello
I have a spouse visa application query
I just received my COA and my wedding date at the registry has been fixed, soon after that we shall book our spouse visa appointment but we're extremely worried about the financial summary.

My fiance (british citizen) earns £15,000pa and while i was on my WHM visa i earned £17,000pa.
But since i've had to leave my job in the past two months due to the WHM visa requirements, he's the sole earner and we have just £10,000 in savings and no properties owned as we're just 25 yrs old.

Would it be advisable to secure a letter from my previous employer stating they will hire me (which they would like to do as the company is expanding)

also i did not work continously on my WHM visa, working full time and part time has come up to 12 months totally. But my employers recently called the homeoffice and they told it has to be 1 yr continous FT employment, and the remaining 1 yr of only holidaying. since i have not done that would that be a breach of my immigration rules on my WHM visa, and be a possible reason for them to reject me???

any advice would be great, thanks