Upvote:2
From the history of UK refusals I've seen on this site and other places, it seems for UK the most important criteria is the applicant's financial circumstances. This is also a reason explained in your refusal letter, so if your financial circumstances improved significantly - such as the level where you can easily afford a trip to UK - this might be sufficient for approval.
An evidence that you are both settled in Brunei (such as a property lease agreement for one year or so, employment contract etc) would also help establishing the fact that you're not moving back to UK together, and only trying to visit.