If you really want to do a full comparison, I'd also add the following advanced stats:
Felton: TS% - .481
Miller : TS% - .515
Felton: AST% - 32.7
Miller : AST% - 35.1
Felton: STL% - 0.9
Miller : STL% - 2.6
Felton: TOV% - 19.4
Miller : TOV% - 10.7
Felton: ORtg - 98
Miller : ORtg - 113
Felton: DRtg - 102
Miller : DRtg - 96
Felton: WS - .3
Miller : WS - .9
Felton: WS/48 - .075
Miller : WS/48 - .202
Usual small sample size disclaimer, but in Miller's case, other than TOV%, DRtg and WS/48 the numbers are very similar to his career averages and also very similar to the numbers he posted in his two seasons with the Blazers. In Felton's case, the steals are down and turnovers up, but other than that, his advanced stats so far this season aren't that much different than his career averages. They both pretty much are what they are. Miller may be significantly older, but he remains incredibly consistent and shows no signs of declining performance. Felton has been in the league long enough that he's unlikely to show significant improvement.
BNM