Best look inside a 256-color world
Start sharp; do not invent lossless
A lossless slogan is marketing fluff: indexed palettes are lossy by design. High quality GIF results come from sharp PNG or lightly compressed JPEG sources, limited gradients, and raising the quality slider before you shrink dimensions. Double-JPEG mud cannot be restored. If the source is a 640px screenshot, Image Enlarger will not invent detail — it only stretches pixels toward the ~1200px cap.
Smooth motion is delay plus enough frames — not spam
Smooth playback comes from sensible millisecond delay and enough frames to read the action. Dumping 30 near-identical photos just bloats the file. Keep text large, crop dead space so pixels serve the subject, and preview banding on both light and dark backgrounds. Reverse, boomerang, and pingpong can hide a hard cut without adding frames.
Resolution ceiling and a sane size budget
Respect ~1200px max base dimension before encode. When the file bloats, cut resolution first, then frame count, then quality — in that order. Target-size budgeting is a last pass after the loop already looks right, not a substitute for simpler art.