与…相比 and 比 — two ways to compare

規則 A 比 B + adjective — 比 sits INSIDE the sentence: 今年比去年好。
与 A 相比，B… — the whole phrase OPENS the sentence, set off by a comma: 与去年相比，今年好多了。
跟 A 一样 = the same as: 我跟他一样高。 A 一样 needs its 跟 (or 和).
相对来说 = relatively speaking, opening a sentence with nothing named to compare against.
No 很 or 非常 after 比; to intensify use 更, or add the margin afterwards.