Clear water repellents of the sort you’ve used do retain the like-new colour of wood, but only for a short time. Since they don’t offer much protection against the UV rays of the sun, repellents can’t prevent the development of a dull, grey, weathered look. I have yet to find any outdoor wood furniture finishing product that preserves the bright colour of new wood for more than a season without attention.

At this stage, you have a couple of options:

1. You could give your furniture another coat of repellent, then put it outside in a shady spot and enjoy them while they slowly turn grey.
2. Another approach involves coating the furniture with exterior-grade oil every spring. Circa 1850 Tung ‘N Teak Oil is one product that I know works well. It imparts a brown colour to the wood, but repeated application every year does hold off the grey better than most products.

Whatever you do, don’t use any finish that forms a surface film. These inevitably peel, and that makes a real mess in all the nooks and crannies of a bench, chairs, and other furniture. Latest results from an ongoing Consumer Reports deck treatment survey places Olympic Water Guard 57560C at the top of the list for clear outdoor wood treatments.