How to get an reusable rocket

At the risk of getting a reaction that goes something like this: "If you're so smart, why don't you do this yourself", I offer this proposition for a reusable rocket design.

Rather than using a RP1/LOX type rocket that Musk is planning to use for his reusable rocket second stage, why not use a LH2/LOX rocket instead?  Here are the calculations that would add 40% of mass to each stage and still get the same payload to orbit.

Instead of going to orbit the way he does, you would slow down the first stage and speed up the second.  The second stage, by virtue of having the higher ISP rocket design, will be able to make up the difference and do it with less propellant.  Happily, that gives us margin on both stages for more mass to do the reusable thingy.

Now these calculations are estimates and are subject to error.  However, even with error, it does not refute my basic point.  That is this:  using a higher ISP rocket for the second stage improves the odds of getting a reusable design.

Using the rule of adding 40% to the mass for a reusable rocket, this procedure is capable of delivering that extra mass in two ways: 1) by using less mass in the first stage and 2) by using less mass in the second stage due to higher ISP.  Compare the ISP of the second stage Falcon (column D) with the second stage modified ( Column G).  The difference is over 4k kgs, which is added to the dry mass in order to make it reusable.  The first stage Falcon has 47.9k kg of propellant cut off, and then adds back in 10k kg in dry mass for reusability.  This slows down the first stage velocity, but the higher performance 2nd stage can make up the velocity and still add mass for reusability.

A hydrogen rocket doesn't help that much when lifted off the ground.  It gains the most advantage as a second stage.  The Apollo Era Saturn V did this.

This isn't a mission to the moon though, as the Saturn V fulfilled a different set of parameters.

Note that the entire rocket now weighs 37900 kg less.  The higher ISP lets us economize on the use of propellant.

Update:

A couple ideas occurred to me since I posted this ditty.  One, that you could add propellant back into the first stage, while keeping everything else constant.  That gives the rocket the same mass it has at present.  Two, with the extra mass added in, you could use that for reusability of the first stage.

One problem, though.  There's not enough mass.  A proposition to solve that problem would be to make it an airbreather on the way down.  That would enable the use of more propellant so as to execute a reverse trajectory on the way down.  That may be an oversimplification, so take that under advisement.

As for the second stage, you may have the same problem, with the same proposed solution.