Swithing from a 44 to a 53

the only issue is it's lack of versatility - but that's all based on your comfort level.
I've found it difficult to defend tripes / trips as well as disguising / altering coverages and / or fronts with the 53 personnel.

Coach, I think you're on the right track particularly if you see 80% run with a lot of inside zone, iso, and trap. A couple comments:

(1) From a purely coaching standpoint, by moving from a 4-4 to the 5-3 double eagle front, in reality, all you have to do it to replace one ILB with a NG. A couple of shades change (weak 1 changes to a 3, strong 7 changes to a 9), but otherwise, you should be able to run your defense in much the same way as your old defense. This will be helpful, particularly if your coaching staff is comfortable with the 4-4.

(2) Against the run, I'd be a little concerned with susceptibility to the outside run to the strong side with the Sam in a 50 technique (you mentioned that you see wing-t, so the sweep might be tough to stop). You might think about stacking Sam behind your SE in a 90 technique, where he is in a better position to both force v. outside runs and fill v. off tackle runs. Also, as noted above, this would probably make it easier for your OLB coach to teach because it is pretty close the the OLB tech in the 4-4.

(3) Similarly, against the pass, the Sam might have a tough time getting to the flat from a 50 tech, so stacking him might help. Also because you're playing your WE in a 5 tech, I was wondering whether you wanted to have the capability to bring only a 4 man rush with your cover 3 (using the WE as the flat defender) or if you planned to generally play a 3 deep/3 underneath coverage with a 5 man rush. If you bring 5, I think you might have to incorporate some man techniques with your CB's (CB’s handle WR’s on 3 step flat routes) and OLB’s (OLB’s handle backs releasing on flat routes) because it might be tough for the OLB's to get to the flats with their tight alignment.

(4) Finally, with respect to spread sets, you might consult some of the 3-3 coaches on this board because their defense looks like a 5-3 when playing v. a tight or pro front, but has the flexibility to spread out with spread sets. Good Luck!