I don't see anything that concerning about Breida as a receiving back. Understand that the 49ers always used a stable of running backs and alternated out constantly, and more than one in that stable was best known for being a third down back.
I'm more concerned with finding a worthwhile running game to limit the third and longs to begin with.
Let's be honest, unless Laird is a great special teams contributor he's not gonna be on this roster. It was nice to have a guy who could just follow his blocks and execute after all we went through last year, but the dude has less lateral quickness than Kalen Ballage, whose practically a statue, and when you're a tiny guy without physical skills you need to execute at a near perfect rate (which is what Wes Welker, a much more skilled player, did to stick on the field). Laird started botching his chances late in the year. He's gone, and a guy like him should just be happy circumstances lined up for him to get to play a season in the NFL.