The following is an attempt to recreate past championship teams by assembling a team with today's players that have the most similar stats to the players of past teams that have won it all. I'll be starting things with the 07/08 Celtics and their 10 players that played the most minutes during the regular season.
Note: All stats are from basketball reference and I'll be using per-game stats for the most part but considering advance stats for tiebreakers
The Starting 5
Paul Pierce 19.6/5.1/4.5/1.3/0.5 59.9 TS%, the closest equivalent is Khris Middelton 20.2/5.4/4.3/1.3/0.2 56.6 TS%
-A little bit surprising since Pierce was seen as a tier above Middelton respective to their competition but understandable given their team situation.
Ray Allen 17.4/3.7/3.1/0.9/0.2 58.4 TS%, closest equivalent is Evan Fournier 17.9/3.1/2.9/0.9/0.3 57.7 TS%.
-Pretty much a similar case with Pierce and Middelton
Kevin Garnett 18.8/9.2/3.4/1.4/1.3 58.8 TS%, the closest equivalent is Marc Gasol 18.0/8.6/3.9/0.7/1.5 52.9 TS%
-So far the biggest statistical reach but in terms of playstyle and role this is the best equivalent so far. KG was the DPOY that year and Gasol is also a former DPOY. Both players are versatile scorers and can run an offense with their elite passing from the post. The main difference would be KG was much more athletic while Gasol is bigger.
Rajon Rondo 10.6/4.2/5.1/1.7/0.2 51.5 TS% closest equivalent is Ricky Rubio 11.9/4.2/5.1/1.5/0.1 52 TS%
-Both players' biggest strength is passing and court vision. Neither can shoot that well (albeit Rubio has been shooting amazingly in the past few games). The main difference is experience, Rubio is on his 7th season while Rondo was on his second season.
Kendrick Perkins 6.9/6.1/1.1/0.4/1.5 63.2 TS%, the closest equivalent is Mason Plumlee 7.4/6.0/2.0/0.7/1.2 56.3 TS%.
-Plumlee is a better passer and more athletic, and Perkins is a better defender. Both take most of their shots within 5 ft and are more known for their physical traits than their skills.
The next 5
James Posey 7.4/4.4/1.5/1.0/0.3 58.7 TS% ~ David Nwaba 7.1/4.4/1.2/0.8/0.5 56.7 TS%
Eddie House 7.5/2.1/1.9/0.8/0.1 53.4 TS% ~ Bryn Forbes 7.8/1.5/1.0/1.3/0.4 53.3 TS% (Isiah Whitehead was a closer equivalent but has only played 12 games this year)
Tony Allen 6.6/2.2/1.5/0.8/0.3 52.7 TS% ~ Norman Powell 6.6/1.8/1.6/0.7/0.3 49.7 TS% (Honestly could either be him or Pat Connaughton 6.5/2.2/1.3/0.2/0.3 55.9 TS%)
Leon Powe 7.9/4.1/0.3/0.3/0.3 62.9 TS% ~ Jarret Allen 7.1/4.8/0.5/0.4/0.8 62.7 TS%
Glen Davis 4.3/3.0/0.4/0.4/0.3 54.5 TS% ~ Zach Collins 4.2/3.3/0.7/0.3/0.5 47.1 TS%
How good is today's version of the 07/08 Celtics?
Are they a playoff team?
-On paper, they an arguably a better team than the current 7-8 seeds in the East and the 8th seed in the West. However, what they have going for them is that they have personnel that in theory would gel together quite well. I'd say at their worst they are the 9th seed on either conference and at their best, the 4th seed in the East, most likely closer to former with around 42 to 52 wins.
Can they beat the current champions (16/17 Warriors) in a 7 game series?
-Short answer, No. This team is pretty solid offensively and defensively but it's quite obvious the Warriors have much more firepower on both ends. In my opinion, the Warriors would sweep this match up and the closest game would probably be decided by 8 or more points.
Can they beat the 07/08 Celtics in a 7 game series?
-One thing people forget about this Celtics team is the fact that they didn't exactly dominate any series, most notably losing every road game in the first 2 rounds. I'd say their mirror team could give them a bit of a challenge especially since they match up against them pretty well but they'd still come up short due to the Celtics much more superior defense. I'd predict the Celtics win in 6 and have their losses come within 5 points.
What's their ceiling in the playoffs
-2nd round exit on either conference, again they are a solid team but they just don't have enough firepower on either end to get far in the playoffs.
Note my predictions are just my own interpretation and opinion, feel free to comment otherwise