Well, at this point it looks like we'll be lucky to get one of those two. Harrington looks like he's going to the Warriors, and even if that falls through we'd still need to figure out a sign and trade for him (since I doubt he settles for the MLE). I'd imagine Bonzi will resign with Sacramento, but it's still up in the air. Unfortunately, we've only got the MLE to offer, and I doubt that that is enough.
If we were able to add both those guys, we'd definitely be back in the hunt to a certain extent. However, I would rather see the Pacers pursue other options.
In my mind, the Pacers' biggest needs are a go to scorer to complement JO (it's unlikely that we'll fill this need this offseason or any time soon really), a good outside shooter (obviously we lost Peja, and Sarunas did not work last season, though I'm still hopeful), and a good big man to pair with Jermaine. I think the last need is the one we can most easily fill. Kenyon Martin is availiable, but I doubt the Simons want to pay his huge remaining contract. Troy Murphy might work as well, though I don't know if the Warriors are willing to move him. Maybe Magloire, but he's a free agent next year and I can't see us paying him as much as he wants.
So, I'd like to see a Pacers lineup like this (assuming we trade Tinsley and Jackson for K-Mart)
Daniels/Fred Jones?/James White
I think that would be a very good defensive team. It would struggle at times offensively (much like the Pacers do now).