The phrase "a reasonable first" is correct and usable in written English.
It can be used when discussing an initial step or action that is sensible or appropriate in a given context.
Example: "This proposal is a reasonable first step towards addressing the issues we face in our community."
Alternatives: "a sensible initial" or "a logical starting".
We feel that this is a reasonable first approximation of phenomena such as lithic technology for two reasons.
Half as much again is a reasonable first guess.
"This is a reasonable first step," said Mr. Robins, who heads the Alan E. Voorhees Transportation Center at Rutgers University.
Failure to distinguish and inhibit noise signals is a reasonable first guess about a variety of hallucinogenic effects".
"We had a reasonable first minute and then we just had nothing left to give," said Redgrave.
A reasonable first cut might be that it's good news for Mitt Romney, since he is thought to have a lead among early voters.
From a tax standpoint, this has been "a reasonable first step" in a college-financing plan, said Sidney Kess, a New York tax lawyer and accountant.
"They are also varied enough genetically to make a reasonable first step towards a full reintroduction if that was the decision of the Scottish government".
"The experience sampling work is a reasonable first step, but only that; the claims need to be followed up and backed up by objective studies".
A reasonable first impulse is to try to identify all the sound sources; the inevitable second impulse is to marvel at how well he has chopped up and rearranged them into units of rhythm.
"The attorney general's proposal is a reasonable first step in regaining control over illegal immigration in the United States, which is currently out of control," said Representative F. James Sensenbrenner Jr., a Wisconsin Republican who leads the House Judiciary Committee.
