An MBA will probably benefit you in the climb up the corporate ladder, but will take you further away from code. It also probably wont start helping until later on in life.
A Masters is great - the problem is that an MSc in Computer Science will focus very much on the science side, which is not much use to businesses. If you could choose an MSc that had more relevance to the business context, then it could help, but then again, only in that specific context.
My advice - look for a course, masters or otherwise, that focuses more on software engineering and less on computer science. Or look at the Microsoft certifications - MCSE, all that kind of stuff. If you only want to study something to boost your career, study something that is not purely theory, but about applying computer science and possibly other disciplines to the IT industry. When you start working, you'll be exposed to ideas and concepts that probably had little or no relevance to you. You've probably never been handed a project whose original developer has since left. Or taken over maintenance of a badly architected system and started thinking how much can you refactor before you simply start introducing more problems. Hopefully you have at least had source control experience.
All of these maintenance issues might get a passing mention in a computer science class, but you really learn them on the job. I like to think of it as the engineering side of IT - what happens when you apply computer science to the business context.
So..... what I would do, if I were you.
Do your honours, definitely. Put a lot of work into, and choose subjects both that are relevant to you and relevant to the business. I think only one or two employers have ever asked me about my honours work. It never comes up. I did computer graphics, artificial intelligence, enterprise java, distributed and parallel computing, advanced networking, and advanced computer architecture. The only one of those I use on a day to day basis is computer graphics, and artificial intelligence and advanced computer architecture was the most interesting to me. Anyway, point being, no employer has ever decided whether or not to employ me based on those choices.
As for Masters, I would say, only do it if it is something you are passionate about. If there is a research subject that you think is really interesting, pursue it. Study Masters for the experience itself, not for what you think the benefit might be. Unless the Masters is in a more engineering related discipline - and you find that interesting too - then maybe thats okay.
During Honours, involve yourself in side projects. Start working on something open source. Write a game. Something like that. Employers love that stuff. It makes them think they can lock you up in the office and you will work 24/7.
If no exciting research subject grabs you, then start work somewhere. Re-evaluate whether you want to study after 1 year - you will be amazed at how much you have learned.