I actually find Bradley somewhat hard to predict for next season. I like to look at a team's statistical profile and try to project how it might change based on the personnel changes. Here's all the numbers for Bradley:
http://kenpom.com/sr.php?team=Bradley&y=2008
First, a look at the offensive side. Bradley had a very good offense last season - they finished 45th in adjusted offensive efficiency. The strengths of the offense were 3-point shooting and ball movement. Bradley was 28th in the nation in terms of the proportion of their shots taken from downtown, and shot them at a 37.4% clip - good for 73rd in the nation. Bradley was pretty average in terms of turnovers, two-point shooting, and getting to the foul line, and was below average in terms of offensive rebounding.
I see a slight dropoff in 3-point shooting, simply because Ruffin and Crouch shot and made so many of them. I do expect improvement from Warren and Maniscalco, and the new guards sound like good shooters, but I still think that facet of the offense won't be quite as good.
I think offensive rebounding should improve quite a bit, just by playing the returning big guys more (Collins, Singh, and Austin). If the big guys can increase their minutes while getting their turnovers under control, the offensive rebounding improvement will help make up for some of the lost shooting. Also, the returning big guys all shoot 60%+ from the field, so the 2-point shooting figures to improve as well.
Overall, I expect a slight dropoff offensively for Bradley this year, simply because Ruffin and Crouch were both such good offensive players. Let's say the Bradley offense drops from 45th to 60th (just a guess, really, but seems reasonable to me).
Defensively, Bradley finished 143rd in the nation in adjusted efficiency - this is the side that needs real improvement. The only real strength was getting steals, in which Bradley finished 66th. Every other category was below-average, but the worst ones were 3-point FG defense, defensive rebounding, and shotblocking. I've got to think that the latter two can be shored up simply by giving more minutes to big men, especially David Collins. Anthony Thompson may prove to be a major shotblocking factor as well. I do think the Bradley defense will improve, but the real question is how much. I think a reasonable expectation would be for the defensive to be something like 90th in the nation, which is in line with past Jim Les teams (except for the excellent Sweet Sixteen team).
Combining these offensive (60th) and defensive (90th) efficiencies would give you a team somewhere in the 70-75th range. So, that would be my baseline expectation, which with normal luck would be an NIT team. I think Bradley definitely has upside beyond that, and could turn into MVC champs and an NCAA Tournament team if things break right.
I have a feeling that this countdown will put Bradley worse than that, simply because Ruffin and Crouch are high-profile losses. I think the returning players form a solid enough core that not much is even needed from the new players to have a top 100 team.