Seeding with Brillion grass seeder

I’m looking at purchasing a Brillion grass seeder to do my seeding this year. In the past, I was using a JD BA drill and just letting the seed drop from the grass seed box, then harrow then using the land roller. Seeding alfalfa and grasses with small and large seeds makes for inconsistent fields. 
the field has been plowed in the past 2 years, so ground is soft. I have been discing in my fertilizer prior to seeding . 
I'm wondering if a person needs to use a land roller prior to seeding with a Brillion seeder, or after seeding. 
also, do people harrow after seeding to get rid of the tractor tire imprints to level the field. 
my soil type is dark grey. 
thanks for the feedback. 

Seeding with Brillion grass seeder