Personalised corporate gifts are the best bet. Even though they may cost a little more, they convey your message effectively.
Stick to basics:
It makes sense to maintain some formality during gifting and therefore you can skip frills in terms of artistic wrappers.
Avoid repeating the same gift for the same customer every year. A gift loses its value if it is given again. Always buy different gifts for old and new clients.
Photo frames, mugs, ceramic ware, crystal ware and leather products are good options. Ensure their quality and also store them with care to avoid breakage.