I suspect that by its nature, lower-end RTW/OTR has to follow trends to some degree, which probably makes it less "timeless." I suspect that "timeless" really means "well-executed but middle-of-the-road design."
IE, for a jacket, not too slim but not boxy; a bit of drape but not much; a bit of shoulder padding but not much; natural shoulders, or mildly roped, but maybe not shirt-sleeve; medium-width lapels; medium-high gorge; two-button or maybe 3-roll-2; flapped pockets but maybe no ticket pocket; two vents; just barely covers the butt; well-structured, but not too structured, and not close to unstructured; a classic cloth color (darker gray or navy) in a classic weave and a classic micro-pattern or no pattern; four button sleeves; and with less waist suppression, though maybe not an actual sack cut, etc. For pants, probably something between mid- and high-rise, modest taper, fairly full, probably single pleat, half- or full break, with interior buttons for braces and your choice of belt loops or side adjusters, and cut generously enough to need it. Does that roughly describe what you're looking for, OP?
But to find _all_ of that OTR is always a bit hard. Today's style is more on the slim-fit side, and with smaller lapels, and more waist suppression. Many makers are doing shirt-sleeve shoulders, almost no shoulder padding, less structure, less / no drape, and shorter. For pants, probably mid-low rise today, fairly slim, quite tapered, and with no break or mild break, and often without buttons for braces. That's what people want so that's what makers make. Especially at the lower end of the budget.
IE, for a jacket, not too slim but not boxy; a bit of drape but not much; a bit of shoulder padding but not much; natural shoulders, or mildly roped, but maybe not shirt-sleeve; medium-width lapels; medium-high gorge; two-button or maybe 3-roll-2; flapped pockets but maybe no ticket pocket; two vents; just barely covers the butt; well-structured, but not too structured, and not close to unstructured; a classic cloth color (darker gray or navy) in a classic weave and a classic micro-pattern or no pattern; four button sleeves; and with less waist suppression, though maybe not an actual sack cut, etc. For pants, probably something between mid- and high-rise, modest taper, fairly full, probably single pleat, half- or full break, with interior buttons for braces and your choice of belt loops or side adjusters, and cut generously enough to need it. Does that roughly describe what you're looking for, OP?
But to find _all_ of that OTR is always a bit hard. Today's style is more on the slim-fit side, and with smaller lapels, and more waist suppression. Many makers are doing shirt-sleeve shoulders, almost no shoulder padding, less structure, less / no drape, and shorter. For pants, probably mid-low rise today, fairly slim, quite tapered, and with no break or mild break, and often without buttons for braces. That's what people want so that's what makers make. Especially at the lower end of the budget.