I guess so.

高ーい	8753	11.8%
たかーい	30016	40.5%
たっけー	19700	26.6%
たっかーい	1755	2.4%
たっかい	13809	18.7% (example from google: "えらいたっかいなー（15分1000円 イベント価格ですが…） など言ってましたが、止まるところを知らないほどによく話してくれ、最後には、宝くじの当たり券の話やここ一")

OK to include たっけー?

@@ -13,0 +14,4 @@
+<k_ele>
+<keb>高ーい</keb>
+<ke_inf>&sK;</ke_inf>
+</k_ele>
@@ -18,0 +23,12 @@
+</r_ele>
+<r_ele>
+<reb>たかーい</reb>
+<re_inf>&sk;</re_inf>
+</r_ele>
+<r_ele>
+<reb>たっけー</reb>
+<re_inf>&sk;</re_inf>
+</r_ele>
+<r_ele>
+<reb>たっかーい</reb>
+<re_inf>&sk;</re_inf>

I think it's best to think of it as an entry-wide x-ref (a feature that will probably be added to JMdict: NG).
I've reindexed that sentence and chosen a new one for sense 1.

I don't think the antonym cross reference to sense 1 of 低い is right.
As I wrote last year in the entry for 低い:
  "Right now it seems we have
   低い[1] <-> 高い[2,3]
   低い[3] <-> 高い[1] (and possibly 低い[2])
   低い[4] <-> 高い[4,5]"

The current priority example sentence indexed to sense 01 of 高い seems like it should be sense 03 instead. It's definitely not high/tall.
  銀行はリスクの高い顧客へのローンには高い金利をつける。
  Banks charge higher interest on loans to risky customers.

Google N-gram Corpus Counts
╭─ーーー─┬────────────╮
│ 高い　 │ 62,758,210 │
│ 高価い │      4,201 │ - [iK] to [sK]
│ たかい │    711,529 │
╰─ーーー─┴────────────╯

@@ -12 +12 @@
-<ke_inf>&iK;</ke_inf>
+<ke_inf>&sK;</ke_inf>
@@ -21 +20,0 @@
-<stagk>高い</stagk>