That looks great. I find that linseed oil yellows quite a bit on light timber, but we've still used it a lot on on outdoor planters. I prefer decking oil, but what ever you use, you'll need to sand and re-coat every now and then. I never use varnish on outdoor stuff as it always ends up flaking off. If you want to try out some higher end oil/waxes try Whittle Waxes Exterior Oil (online).