It can be rough on those smaller tiller boats due to their lower weight handling.
You put the motor, gas can and a person right in the back they are going to want to run nose high until you are on plane. That all goes away with a larger boat.
I ran 16, 17 and 18 foot tillers on Great Bear and never had those issues (even when running alone with my fat a 30 hp OB and 15 gallons of gas under the back seat).
My first boat a little 12' tinny and 5 1/2 Johnson would ride nose high and I'm pretty sure my 8' inflatable with 4 hp Merc will probably ride nose high, but I won't know until late May or early June when I get a chance to run her for the first time.