Litigation is hectic, busy, stressful, but also exciting. It would be hard to maintain a lot of time for learning or family. However, if you prioritize right (get up early to learn and learn when you come home), you can do it.
Prosecution is a little more predictable, but there is still a certain amount of billables you must meet, which means long days.
Also, while it may be slightly easier to get a job in a big firm with patent law, it still is difficult. You need to go to a good law school and get good grades. Also, in some ways, your science degree limits you. Firms will not consider you for general positions, which is what they are recruiting for during on campus recruiting. You get placed in a box very easily. While there are certain patent law job fairs, it still is not easy getting a job.