Now is the time for your squad to get better. Free agency is upon us, and for a few teams — namely Cleveland, the Lakers, Boston, Phoenix, Detroit, Houston, Indiana, Miami and New Jersey — this offseason is especially crucial, as they have either aging superstars or superstars in their prime who need to be kept happy via some significant roster moves. So who’s out there? Here are the best available free agents in the Class of ’07 …

Rashard Lewis — Over the course of the season emerged as the top free agent in this year’s class. He’s a relatively young (turns 28 in August) yet experienced 6-foot-10 All-Star caliber shooter (22 ppg, 6 rpg) who creates a matchup problem for most wings in the League. Word is Orlando, Charlotte, New York, Boston, Houston and Miami are all in the sweepstakes. And Rashard still hasn’t ruled out re-signing with the Sonics and showing Kevin Durant the ropes.

Chauncey Billups — He didn’t have his best postseason, particularly against the Cavs in the conference finals. And he’s getting up there in age (turns 31 in September) and, more importantly wear-and-tear (deep playoff runs every year). But C-Billups is still one of the Top 5 or 10 point guards in the League. Odds are he’s staying with the Pistons, but there are a handful of teams who should at least try their hardest to sway C-Billups their way.

Gerald Wallace — One of the game’s most dynamic athletes and energetic players, Crash isn’t a household name yet, but those in the know are all over him. Wallace (18.1 ppg, 7.2 rpg, 2.0 spg) rebounds, plays D and plays his butt off every night. The Mavs reportedly have him at the top of their list, but the Bobcats will try hard to keep him around.

Grant Hill — He played 65 games and a playoff series this year, which is like Iron Man status given his recent history. Hill will be 35 when the season starts and is always an injury risk, but he can still get it done (14.4 ppg) if he’s in a situation where he’s not expected to play a lot of minutes and can afford to take days off here and there. He’s only interested in a getting a ring at this point, so only the big dogs (Spurs, Suns, Pistons) will be in the running.

Mo Williams — Good season (17.3 ppg, 6.1 apg, 4.8 rpg) for a bad team, so maybe teams won’t straight-up break the bank for Mo due to the Shareef Abdur-Rahim Factor. Still, he’s the second-best point guard on the market after Billups. Both L.A. squad could use him, as could Cleveland and a handful of other teams.

Darko Milicic — He’ll always been known as the guy who was picked ahead of ‘Melo, Bosh and D-Wade, but Darko isn’t bad and actually has a lot of potential. Young, 7-foot lefties (he’s 21) who can score and block shots are always coveted. So far it looks like Orlando will re-sign him, but could package him in a sign-and-trade offer for Rashard Lewis.

Brevin Knight — On the low, he’s been one of the League’s top assist guys for the last few years and is the reason Ray Felton could never relax in Charlotte. But Brevin can’t seem to stay healthy, so you wonder how hard a team will pursue him knowing it’s highly likely he’ll give you less than 70 games.

Mikki Moore — After a journeyman run that took him all over the world, Mikki found the right fit in Jersey this year (9.8 ppg, 5.1 rpg) and it about to cash in.

Andres Nocioni — Toughness, outside shooting and defense. Noce brings that to a squad, plus he’s got some postseason and international championship experience. Nocioni (14.1 ppg, 5.7 rpg) is a restricted free agent, so look for the Bulls to match any offer for him that isn’t out of this world.

Steve Francis — It’s no secret the Blazers want to buyout Steve’s contract ASAP, meaning he’ll be available for anyone that wants him this summer. It wasn’t that long ago that Franchise was one of the 10 or 15 best ballplayers in the world. Yeah, he’s fallen off big-time, but he showed flashes last year that he can still be a terror; he scored 20-plus points in each of the season’s last four games, had five other 20-point nights during a year where he only played 44 games total. And he hung 39 on the Nets in a preseason game.

Chris Webber — The Gollum thing (“I want the precious!”) with the Pistons didn’t work, so like Grant Hill, C-Webb is in a position where he still has a little gas in the tank and is only playing to get that championship. But unlike Hill, who’s a great locker-room guy, Webber’s rep is the exact opposite. A happy-family bunch like the Spurs or Suns doesn’t need that in their life.

Jerry Stackhouse — Another aging guy (going on 33), Stack still does one thing well; drop buckets. Teams looking for a bench scorer to put them over the top (that’s you, Cleveland and Denver) should give him a long look.

Anderson Varejao — It’s a weak year for free-agent bigs, but AV is one of the standouts. Forget the flopping and the poor decision-making for a minute and remember that the dude hustles hard and rebounds. We’re pulling for him to end up on the same team with Joakim Noah, just so we can prove they’re not the same person.

Others to look at: Desmond Mason, Morris Peterson, Earl Boykins, James Posey, Smush Parker, Matt Barnes, Mickael Pietrus, Steve Blake, Ruben Patterson, Andray Blatche.