There are different filing statuses to enable different types of taxpayers to determine their requirement to file a tax return and to enable different tax payers to claim certain applicable credits as well as deductions.
No there is no need to eliminate any status. Currently there are five filing statuses – single, married filing jointly, married filing separately, head of household and qualifying widow with dependent child. As each of the status serves a different category of taxpayer there is need for the different filing statuses and none should be eliminated.
For example in case of married filing jointly combined income of the couple is reported and combined allowable expenses are deducted. This status will see higher deductions, lower taxes and applicable tax benefits (26 U.S. Code 6013). The requirements will be different if the status is married but filing separately.