Dear RK,
You are building a competitive foundation for your future applications and I commend you for thinking this far in advance. It is hard to comment on your chances at any school at this point without a GMAT score and being in the middle of your undergraduate studies. It is great to see that you are establishing a strong work ethic and have pursued your interests. You do not have "excessive experience" by any stretch. These are all important experiences and will be evaluated; however, the years of work experience for reporting purposes by business schools is defined as full-time, professional experience after completion of a bachelor's degree. The fact that you have been working will serve you well though and can be used to distinguish you from other applicants applying with less than 2 years of work experience.
I encourage you to continue down the path you are on and you will achieve your goals. Prepare well for the GMAT and get that 720+ score as well as continue to earn high marks in your studies. These things will all make you an attractive applicant to any school you apply to when the time comes. Finally, in the event the HBS 2+2 program does not work out, I think you should consider working for a couple of years before applying to business school. Most schools prefer that you spend some time in the workforce. However, if you feel you are ready upon graduation and it makes sense for your career goals, then you should apply to enter direct from college.
Good luck,
Lisa