The aisle widens here, space opens up, and the direct access to the aisle means you have plenty of space to stretch legs. I feel 44C would be an even better seat for a solo traveller, and if you get 44B empty next to you, then you should savour the experience. However, 45C is pretty damm good and very comfortable. As with most economy seats, lumbar support is poor, but otherwise the seat is fine, and big enough for sensible frames.
Sleeping in this seat, as with most, will be challenging at best and impossible at worst. Working is not easy with the relatively limited tray table, so that small wifi allowance will go to waste for your laptop, since anything over 12 inches will struggle to fit. I barely got a 13 inch Asus Zenbook onto the table, and the recline of the seat in front was a serious concern the entire time.