That's a lot of questions ... You can find some of the answers in this thread:
Clint & MalpasoIn it, I quote from Richard Schickel's biography
Clint Eastwood (p. 186):
Clint, acting on [Irving] Leonard's [his business manager's] advice, established his own company, Malpaso, which means "bad step" in Spanish and is also the name of a creek that ran through the property he owned in Carmel at the time. Clint liked the irony implicit in the phrase, but he says that he did not then foresee the company becoming the full-scale production entity that it soon turned into. Rather he and Leonard saw it as a typical loan-out company of the kind the movies' above-the-line talent had begun establishing in the 1950s, partly for their tax advantages, partly because they put their owners in at least nominal charge of their own destinies.
Malpaso was from the beginning Clint's personal production company and basically, all Malpaso productions are Eastwood productions and he usually directs and/or stars in them. There are, however, a few Malpaso productions on which Clint only acted as producer or executive producer or had no formal credit at all. Notably, there was 1995's
The Stars Fell on Henrietta, which was directed by James Keach and starred Robert Duvall and Frances Fisher, at the time Eastwood's companion, and featured his two-year-old daughter with Fisher, Francesca; Clint is credited as producer. More recently, Malpaso is the credited production company on Alison Eastwood's directorial debut,
Rails and Ties (2007). Alison is of course Clint's daughter, but Clint himself does not have a production credit on this project.
You can get a detailed list of films officially credited to Malpaso by searching the Internet Movie Database under the names
"Malpaso Productions" and
"Malpaso Company, The".
I can't tell you for sure how many people the company employs; not many, and they are basically all Clint's close collaborators. There's some information about some recent key personnel in this thread:
malpasoThat thread is five years old, but Robert Lorenz, at least, continues to work with Clint in Malpaso. The presskit for
Changeling has this information about him (he was credited as producer on that film and on
Gran Torino):
ROBERT LORENZ (Produced by) has worked alongside filmmaker Clint Eastwood for almost 14 years. He currently oversees all aspects of the motion pictures produced at Eastwood’s company, Malpaso Productions, encompassing development, production, marketing and distribution.
Judie Hoyt doesn't seem to be credited on either of Eastwood's 2008 films, but as recently as
Letters from Iwo Jima (2006), she was credited as "production executive: Malpaso."
Another thread you might want to check is:
Clint and his Malpaso Company... which has a (very short) list of Clint's
non-Malpaso films since he started the company in 1968, including the lowdown on
Paint Your Wagon (is it or isn't it?).
Back to your questions ...
Does it give Clint more control over his movies, for example, even though he may not have directed a certain movie, does he still get a lot of say if Malpaso is involved?
It's safe to say that it gives Clint near-total control over his movies, at least since that
Paint Your Wagon experience, and for the ones he doesn't direct himself ... either the director does what Clint wants, or he never works with Clint again (and in at least two cases, he wasn't allowed to continue as director on the particular film).
Is it similar to MGM and Universal?
No, not at all. Those are huge film studios, which have their own production facilities and often also provide financial backing, studio facilities and distribution for the film projects of small production companies such as Malpaso. Ever since
Dirty Harry in 1971, Malpaso has had a working relationship with another big studio, Warner Bros., being physically located on the Warner lot in Burbank.
Changeling, however, was distributed not by Warners, but by Universal, apparently because it was originally a Ron Howard project (he dropped out to work on
Frost/Nixon, but his company Imagine Entertainment and his usual studio partner Universal continued their involvement).
I hope that helps answer your questions!