Ave!

[CaesarAugustus]

Well, a really good reason not to set the division under Hadrian. Hereafter some maps:

Under Hadrianus:

https://www.romanempire.cloud/history?l=...ivers=true

Under Marcus Aurelius:

https://www.romanempire.cloud/history?l=...ivers=true

Under Caracalla:

https://www.romanempire.cloud/history?l=...ivers=true

With Hadrianus the empire did not stopped the expansion. The expansion in middle Europe was stopped by Commodus, but the empire continued the expansion in the East. Also, in the south the Limes Tripolitanus was significantly expanded (an expansion that also Hadrianus continued). Also, we can consider that a great part of the "greatest expansion" of the Roman Empire under Trajan, was not kept until his death, but already when he was alive part of the territories were left under a client kingdom, taken back under Marcu Aurelius, Septimius Severus or Caracalla.
And there are also other places were the empire advanced, for example in the Limes Transalutanus in Dacia, or in Caledonia were there were several attempts to penetrate, finally creating the Votadini client kingdom.

So, with Hadrian the Empire did not stopped the expansion, simply started a reorganization, that in Dacia was also badly thought out.