Think my teeth in general will be slightly more yellow than before. which teeth bleaching/whitening works better?

Ask your dentist: There are many tooth whitening materials and different methods. You should discuss your options with a dentist who can actually see your teeth personally to give you your options and suggest what would be the best method for you. There is no general one best agent or method. It really does depend upon your specific needs and preferences.

Use ADA material: Most of the otc formulations such as crest white strips are fine for whitening your teeth. Please avoid mall kiosks or spas as they do not understand causes of discolored teeth. Alternatively trays made be a dentist are the most efficient manner of whitening teeth used with carbamide peroxide gel. Good luck!