Robert Satloff makes a convincing case that the departure of Bashar al-Assad would be beneficial not only to the oppressed people of Syria, but to Western policymakers as well:
It is difficult to imagine any conceivable successor to Asad who would pursue more problematic or troublesome policies. Indeed, history shows that post-transition regimes tend to be preoccupied with internal problems and therefore do not pursue aggressive behavior toward their neighbors. The Syrian army under Asad's successor would likewise focus on ensuring domestic security, rather than seeking external ventures for which Syria might pay a heavy price.
He goes on:
The straw man of the Syrian Muslim Brotherhood: In a post-Asad world, the ruler of Syria -- "the devil we don't know" -- is likely to be Sunni and, in comparison to Asad, more secular and politically moderate. Whatever his political inclinations, chances are unlikely that a Sunni leader would maintain Asad's close ties with Shiite Iran and Hizballah. Still, even if one assumes, for argument's sake, that the Syrian Muslim Brotherhood would dominate a new regime, such a government would still likely be less problematic than Asad's. The Brotherhood is a relatively weak movement in Syria -- many of its members have been killed or locked away in Asad's prisons, and the remainder is abroad. Furthermore, Syria has a secular majority, and a Muslim Brotherhood government would be constrained by that reality. Even in a worse-case scenario of a powerful and effective Sunni fundamentalist regime in Damascus, one should not forget the influence of a strong deterrent, such as Israel has displayed since 2006 toward Hizballah, itself a well-armed, radical Islamist movement.