To date electronics is still one of the most if not the most saturated market to get in to. But if you want to pursue this niche you can try selling accessories for starters and take it from there. If you were that successful with your clothing niche maybe you can apply the same techniques you did to your clothing site to your upcoming electronics site as well :)
Niches are quite specific actually so a niche from my end may not necessarily be a niche at yours. Your best option at finding another viable niche is still market research. But things that can give you ideas for your next niche are:
- hobbies (yours and other people)
- watch out for new trends - things/products that are repeatedly mentioned through various form of media, tv/radio/print ads/magazines
- check your shopping list
You might also like to try using our Research Lab in your niche hunt :)
Hope this helps!