I'm in awe of and intrigued by Sir Ronald Syme's The Augustan Aristocracy – and have to chuckle over things such as "… the opuscule of Velleius Paterculus which swells before the end into a panegyric of Tiberius Caesar." Of course, as always with Syme, the book is quite dense. I wish I had more time.
The book is nearly unaffordable right know, at least on the U.S. market, although I must have hit a window when I purchased it a year or so ago: interested parties might want to check ever so often, especially at AbeBooks.com.
Google Books does have an extensive preview which gives an excellent indication of the scope of the work.
I searched the Internet Archive without success, but did find The Roman Revolution.