I did a similar list back in 2003 when I was watching the series for the second time through. I had read the manga before that, though I don't remember whether I took it into consideration when making the list. In general the anime follows the manga very accurately - if we ignore some blatant filler such as episode 32 (Yotsuya's egg; IIRC even its drawing style differs, so maybe the animators were using it for practice).
Your list corresponds to the B and C ratings in my list; B doesn't advance the main story but still e.g. develops the characters, whereas C is a pure filler episode. Except for a couple of episodes, our lists are similar.
It's interesting to notice that after episode 70 there are no filler episodes, and also on average the ratio of content to filler episodes is much better than in many other anime series. :)
A: Important part of the story
B: Could be skipped but is still worth watching
C: Totally irrevelant
01 A + + +
02 A + + +
03 A + + +
04 A + + +
05 A + + +
06 A + + +
07 A + + +
08 A + + +
09 A + + +
10 A + + +
11 B + +
12 A + + +
13 A + + +
14 A + + +
15 A + + +
16 A + + +
17 A + + +
18 A + + +
19 A + + +
20 B + +
21 B + +
22 A + + +
23 A + + +
24 A + + +
25 A + + +
26 A + + +
27 A + + +
28 B + +
29 C +
30 A + + +
31 A + + +
32 C + not in manga
33 B + +
34 A + + +
35 A + + +
36 C +
37 C +
38 A + + +
39 A + + +
40 A + + +
41 B + +
42 A + + +
43 A + + +
44 C +
45 A + + +
46 C + not in manga
47 B + +
48 A + + +
49 A + + +
50 C +
51 C +
52 A + + +
53 A + + +
54 A + + +
55 A + + +
56 A + + +
57 A + + +
58 A + + +
59 A + + +
60 A + + +
61 A + + +
62 A + + +
63 A + + +
64 A + + +
65 A + + +
66 A + + +
67 A + + +
68 C +
69 B + +
70 A + + +
71 A + + +
72 A + + +
73 A + + +
74 A + + +
75 A + + +
76 A + + +
77 A + + +
78 A + + +
79 A + + +
80 A + + +
81 A + + +
82 A + + +
83 A + + +
84 A + + +
85 A + + +
86 A + + +
87 A + + +
88 A + + +
89 A + + +
90 A + + +
91 A + + +
92 A + + +
93 A + + +
94 A + + +
95 A + + +
96 A + + +