What brands to you have in mind as competitors? Are you going to try to compete with Valextra, Louis Vuitton, ST du Pont, etc.?
"Luxury" is much-overused, but if you're determined to go there it depends much more on marketing and branding, rather than features.
For example, is Rimowa 'luxury'? It's expensive, but I wouldn't put it in the 'luxury' bracket. For me, 'quality' is a much more attractive, err, quality to aspire to. Actually, what will get me interested is value. I'll happily pay quite considerable sums for luggage, but only if it's good value.
In luggage & accessories I would look for;
- Organisation
- Weight
- Finally, materials