A couple of thoughts here:
A) I have a real mixed opinion about freemium. On the one hand, I think the core concept is fair and honest. It lets players get a feel for the 'basics' of a game before they decide to buy into a richer product set (and in this way its like a demo). I also think its a good way to add content to a game and provides a way for players to buy extras without additional expense or hassle - its convenient for players, and good for developers.
I think where freemium falls down is when you start trickle-feeding players content to squeeze more money out of them (I can think of a few F2P MMOs that are perfect examples of how horrible this can become). Another example are the games that come out broken, or with 90% of the content, followed a week later by "add-ons" which should have been part of the original package.
When using the freemium model, I think you have to be very careful with the core quality and content in your initial free release, what add-ons you decide to charge for (or give away for free), and how much you charge - otherwise your game will come off feeling like a rip off and/or drug deal, resulting in alienated players. And for god sakes, avoid skinner boxing your players.. they are not rats! (I won't get into the ethics of that just now.. a topic for another time).
B) As for piracy, its unavoidable. You can't really stop it anymore than you can stop people from rating your product somewhere on the internet, and generating positive or negative comments about it. Your only "full protection" against piracy is probably to have an always-online DRM/remote game-save feature - which looks great on paper, but has been so badly received by players as to be generally despised (SimCity4 anyone?). Alternatives are to use something like a hybrid model such as Starcraft's & Steam's 'offline' mode, but those again are not foolproof. I feel the real advantage with Steam lies almost entirely with marketing and being able to get your game out in front of a lot of players quickly.
This is why I think freemium is a good model for the modern world - if its not abused. It provides a way for players to test games, pay for things they like with minimum hassle, and if combined with online play though a lobby you control, makes it inconvenient for players to pirate your game (they can still do so in solo-play, however).
C) Reviews: This is such a tough one. Being a developer and pouring your heart into something only to have some player rip it apart can be very soul destroying. However, its (again), probably unavoidable that someone, somewhere is going to give your game a 1 star rating, or start a rant, etc. etc. The best you can do here is make a good game and lets your player base see the 'human' side of who you are through posts, chats, etc. Building a community that you moderate and participate in can go a long ways towards this, as well as let you slay any trolls that pop up so they don't poison your community. I am a big fan of free speech, and honestly, bad things are going to happen - know that going in and accept it, but also remember that your player base is like a garden, and you should put some time into feeding and weeding it.
If you don't want to face that task yourself (and I don't blame you), find a community rep to help you out - they can shield you (or your developers) from the worst of the hateful words of trolls and their like.

- Zapgun