The extra type rating probably made you more marketable for the legacy job in whatever algorithm that they used. It also gave you a little bit more confidence knowing you went through another airlines' training without a failure. The legacy HR that hired you was looking at that as a positive as well.
The LCC's are the stepping stones going forward. The bottom 1/3 of every large LCC's pilot group will continually turn over. In 5 years who will the LCC's be hiring? You are going to be flying to south america with a brand new 1500 hr FO sitting in the right seat and you will be a 3-4 yr captain in the left. What leverage for a good contract will your LCC pilot group have? The LCC I came from was hiring regional FO's to trap them for the long term and many were looking at life through rose colored glasses. By the time they are competitive for a legacy job they will have too much invested in the LCC to leave.
For some staying at a LCC is a no brainer. The money won't be as important as living in base, the fast upgrade, or just general QOL. Fortunately, the backlog in hiring at the legacies is starting to loosen up. I think the people getting calls from LCC's will be getting calls from legacies within a few months of each other and it will put an end to this forced jumping around.