I guess if it was me I would get rid of the SPOT and the GPS. I just don't get the utility of the SPOT for a road-based first-world tour (I'm making assumptions here, possibly incorrect). And the GPS is a horrible medium-long distance planning tool. Paper maps are much easier to use. If you really want on-board computerized mapping capability, you could load some mapping software on the laptop, and the iPhone's GPS will be useful in some places as well.
Anyway, I don't mean to be critical, I'm just offering some suggestions. The amount of weight you carry can really have a huge impact on how happy you are on your tour. Don't forget to add up all the extra batteries and chargers and downloading cords when you look at what you are taking.
It's amazing how fast all the stuff can add up. You have to think it all through with all the rest of your gear too - camping, cooking, clothes, tools....
Back to the OP, downloading data about my rides is something I also enjoy for my local road riding. On my last tour, I had to take a laptop (for work), and considered bringing my Garmin 305 and the downloader cord... but it didn't make the cut. Mainly, because it would have meant I felt really obligated (to myself) to not miss any data, which would mean obtaining a daily charge for the Garmin. In the end, I didn't want to put myself through that, so I did what I always do - just write down the miles and stuff off my regular bike computer in a little notebook.
I think everyone has to find their own balance on what they think is important to take with them vs. what they might enjoy but are willing to live without. I think I fall in the middle/heavy range, and am trying to work my way towards lighter.