That seems like a very strange way to conceive of modes, Chris! What you said here is theoretically ok, but I fail to see how that could help a guitarist. First, I believe one must know all of the basic major scale patterns (on the guitar neck), then know the spellings of all 12 major scales. THEN, derive the seven modes from each key. For example: Yes , the key of C Major has no flats or sharps, and should be read as: C D E F G A B (C). then, assign a modal name to each one of these tones:
C= C Ionian
D= D Dorian
E= E Phrygian
F= F Lydian
G= G Mixolydian
A= A Aeolian
B= B Locrian
If You already know how to play in the key of C major all over you fretboard (using your scale patterns), then you can already play in all of these modes!
I don't know ANY guitarists that have transcended scale patterns, and play the guitar by thinking of each key by thinking of sharps and flats! Also, if you are able to do this, then whatever you play will be in a "scale pattern" anyway! There's no way around it. Being aware of the key signature definitely helps, but you must also be aware of the chords and arpeggios, in order to effectively find chord tones and guide tones.
You mention that, if you want to play in E Lydian, you think "5 sharps" . This is really the "parent" key of B Major, but we're playing in the 4th mode of it. Using your method, a guitarist would have to think "I have to play F#, C#, G#, D#, A#". Then he would have to map all of these out on the fretboard. BUT, if a guitarist just thought of playing in the key of B major (while being cognizant of the E major chord tones), he would be able to use his major scale knowledge immediately and quickly. By the way, I am a pianist, and most pianists would think " E Lydian is B Major on the 4th". We don't usually think of the spelling of key signatures, since the major scale patterns already provide us with this information.
I'm not necessarily trying to contradict you, and I know this is a topic that requires much study, but I saw your post and had to put in my two cents worth! Most people (and books, methods) make this way too complex and too bogged down with circuitous theoretical reasoning. There is a much simpler and user-friendly way to do this!