I have a lot to say about Platinum. First of all, the starters are all half decent, and none of them should faint very often when used. The only fainting might occur in the beginning, and only if you lost to your rival. My only starter complaint is the fact that there is yet another Fire/Fighting type as a final evolution starter, despite this starter being rather powerful.
Starter rating - 4/5
Next, the storyline progression. There was a lot of content, and the way that Cyrus gathers all of his followers is just awe inspiring. Also, there is a new character that wasn't introduced in D/P, called Looker. He makes a return in B/W and X/Y, and I was thoroughly impressed with his overall demeanour and character design. How he assists you throughout the game is rather helpful, but not as much as needed sometimes. The introduction of the Distortion World also was a huge difference, and was direly needed. Also, the ability to return to the Distortion World and get the Griseus Orb was a huge help, as Origin Forme Giratina is incredibly powerful. My only complaint is that there is nothing to do post-game. Just go to the battle zone and mess around getting BP and buying rare candies. That is about it, even though you can tag team the battle tower.
Storyline rating - 5/5
Next, the legendaries. I was thoroughly surprised that they would introduce a Ghost-type legendary, also known as the infamous Giratina, which is Ghost/Dragon. I was incredibly impressed by a Steel/Dragon type, which has just introduced a whole new meaning to 'Defence', also known as Dialga. A new speedy special attacker called Palkia was also introduced, and it is Water/Dragon, making it weak to some things, yet super strong against others. The introduction of a new duo, Darkrai and Cresselia, was a strong impression on most people. With Cresselia leaning towards defence, and Darkrai leaning towards attack, this makes them excellent rivals. Another legendary introduced is Heatran; it is a Fire/Steel type and has one weak spot, Ground. Heatran can be captured postgame at Stark Mountain, after defeating Charon, as he attempts to revive Team Galactic. The most powerful legendary was also introduced here, Arceus, and due to its ability to change typing makes it insanely powerful. The last legendaries introduced were Azelf, Uxie, and Mesprit, the pixie trio. Azelf is a rather speedy attacker, able to deal a hit, but not take many hits in return. Uxie can take a lot of damage, but can't lay a scratch on you. Mesprit is the most well-rounded, being able to take a hit and deal one, but it lacks severely in HP and Speed. When combined, it is hard to stop all 3 at once. I find no fault in this generation's legendaries.
Legendaries rating - 5/5
Next, the extra features. They have brought back the Battle Tower, etc. from Pokemon Emerald. That is a huge implement. Next, the introduction of Contests in Hearthome City. That is also huge, and lets you meet Fantia early on in your gym completion quest. Lastly, the Underground. That is just amazing. You can design your own base, check your scores, move it, and much, much more. You can also obtain all 17 plates for Arceus here, as there are 17 types. You can buy stuff in the underground with Spheres, and you can bury Spheres to let them grow up to size 99. You can also place traps that confuse people that activate them, and use tools in your secret base, since traps are not allowed inside secret bases, you use tools. They are traps that go inside your secret bases. Finally, the Survival Area. That is an area next to Stark mountain where you can re-challenge ALL of the gym leaders! How cool is that? Every day, you can re-challege random gym leaders after you beat the game. On Mondays, your rival will battle you right outside the building. How cool is that?!
Extra features rating - 5/5
My final rating - 19/20 - Recommended Highly