There aren't that many low level monsters in the 4e Monster Manual. Sort of noticed it glancing through the book, really noticed it, in the way of a problem, when rolling up monsters randomly. I kept getting the same results. Not absolutely all the time, but enough that I noticed.
Is this necessarily a bad thing, though? I could kind of see where it would be intentional, because there's some value to things being simple and regular and unified at low levels. Low levels is where absolute beginners start, and keeping the options light makes it easier on the DM and on the players -- it's easier to work out effective strategies if the monster side of the equation stays relatively static.
Then, the monster selection expands as they gain levels and proficiency. This causes problems for people who already know what they're doing, but even then, giving the early levels a unified feel, revolving around various kinds of goblins and kobolds and critters, might not be a bad thing. If the lack of selection is really a problem, there's always the allegedly dirt simple de-leveling method, though even full monster creation doesn't look that hard. (Another thing on my to-do list: make some monsters. Preferably weird, crazy ones.)
And, of course, there's always the endless stream of Monster Manuals promised by Wizards, which should solve the problem rather handily. Albeit with more money, but if I'm still playing then I'm likely to get the new and shiny anyway.