If you don't want to try the styles of the 2 kits then using one to suit your tastes would be a good idea. I think the Autumn Amber base malt would be the one that you would use to make a recipe with the hops that you have on hand in some combination or single hop. You might need to add a little...
I tried that kit before and wished that I would have added some more hops. It was decent and a favorite at a party but I would at least split the batch and add some cascade for half of the batch. Or another hop for the other half. This is an opportunity to experiment.
Don't introduce more fermentables now. Let the beer finish up and enjoy it. Make notes for what you would like to improve on it for the next time (increasing ABV, aroma, etc)
I had some old DME (10 months+) that I used for multiple starters for the last 2 BIAB batches and I was pleased with the results. I wouldn't make a beer from a DME that old but a starter is fine.
Just my own experience I notice more aroma on the dry hop, which fades over time...sadly. I have no expbeeriments to compare to but just my observation.
I've also come to appreciate adding hops at the end of the boil (hop stand) to get the hop flavor without the bitterness. Many ways to get to...