I think that many elements of Jake's plan were, well, rushed. But I think he honestly did the very best he could have, and a heckuva lot better than I could have ever done. Hindsight is 20/20, people.
For example, if he knew Tom was going to double-cross him anyway, why not kidnap him and starve out the Yeerk? As sad as it is to say, I think Jake had stopped thinking of Tom as his brother at all by that point, and only as 'the enemy.' He straight-up says in #47 that he "doesn't have a brother anymore." It was that thinking that really got Tom killed, in the end. (Side note: I always think of the one scene Tom actually ever gets as a free human being, clear back in the first book, and he uses that one singular moment of screen-time to go kamikaze-charging at Visser-freaking-Three armed with nothing but his fists; Jake, that's the guy you wrote off as 'not your brother anymore').
Also, I'm sorry, but sending Rachel in alone was a bad move, and should have been avoidable. The auxiliary Animorphs may not have been completely competent in battle yet, but at least a dozen of them could have been sent in along with Rachel (still leaving enough of them on the ground to provide a perfectly adequate distraction; they only really needed six of them as part of the diversion, after all). And with the rest following Rachel onto the Blade Ship, they could have overwhelmed the Yeerks by sheer numbers. Inexperienced or not, more people is better than less people (as was the entire point of the auxiliaries). Attacking Tom didn't have to be a suicide mission.
*sigh* But it's really easy to pick apart Jake's actions, when we are so far away from these events, as readers. The fact is that he was under as much pressure as can possibly have been piled onto one person, fighting for the fate of the world. And this was their last stand, their absolute last desperate chance to avert a total Yeerk domination of Earth. The fact that Jake was able to see all the puzzle pieces as clearly as he did (knowing Tom would double-cross him, coming up with a plan that played off of that fact, knowing they'd need a diversion on the ground to keep the Yeerks from guessing they were already aboard the ship) is frankly amazing. Most people would have simply broken under the pressure, and Earth would have been screwed.
Conclusion: Jake is human. For better or for worse.
Post-conclusion EDIT: Just for the record, I don't actually place the blame on Jake for Rachel's death. I place the blame on Cassie. Her decision to play God with the fate of the world by letting Tom get away with the blue box may have caused a few Yeerks to defect, but, ultimately, THAT was the factor that made such desperate moves on Jake's part even necessary. And, well, I for one truly want to believe that it was just a knee-jerk reaction to seeing Jake almost killing Tom, and it was just something Cassie did without thinking. That would be a perfectly human thing to do. If still the wrong thing. Wrong, but understandably so. But, if what she did was premeditated? If she was intentionally handing over the Animorphs' one game-changing advantage in the hopes that a handful of Yeerks would find their way to their own little happy ending? If that's the case, then I'm with Ax. What Cassie did was unforgivable.