I would say either bike would work great for that purpose. For more info on the CTX1300 you can visit
CTX1300forum.com .
I am only aware of the older Valkyrie. A bit more familiar with the newer Valk. It does have a bigger engine and more power than the CTX. Acceleration is similar. Both are close to the same weight with the CTX being the same as the ST and the Valkyrie just a few lbs more. But they have different ergonomics. A test ride would be required to determine which fits you and your lady best. I felt the CTX has the best stock seat compared to any other bike I've been on and was good for all day (for me). I thought it was way more comfy than my ST1100 ever was. Check on CycleTrader.com for pricing on the CTX1300, which is currently very good even for "new" hold over stock if you can find it or low mile used bikes as well. Either bike should be easy enough for any Honda shop to work on since most of what would be needed is oil and fluid changes and tires. Both are relatively "open" designs compared with the ST or GW (the latest Valk is really a stripped down GL1800).
I do agree with the CTX1300 being a newer bike so less likely to have issues due to being more than 20 years old like the older Valk. And even if you don't do much of your own maintenance you could still change the oil if you choose on the CTX since no plastic needs to be removed. It does have most of the same mechanicals as the ST1300 with a re-tune of the engine to provide a very flat torque curve with strong torque starting at around 2000 rpm. I referred to mine as a cruising/tourer.