Let me add one more attribute to Brahman to the four that I have already mentioned, that of Omni-presence.
The four: Eternal, Changeless, Form-independent, Uninvolved.
Not adding Omni-powerful because there is none other than it to compare with.
Aalso not adding Omni-scient, since I do not agree that knowing is one of the properties of Brahman (ref.: Atanu, Consciousness). Brahman does not need to know anything.You have either written it wrong or understood it wrong, Sankara considered 'the latter' (and not the former), i.e., Saguna Brahman, to exist in the lesser reality (Vyavaharika) and not in the absolute reality (Parmarthika).
It is for you to decide whether Advaita is for you or not. It is not for many Hindus too. Actually, Madhvacharya (Dvaita) and Chaitanya Mahaprabhu (Hare-Krishnas) considered it to be criminal.
"The article also says that according to the Bhagavad Gita, Saguna Brahman is immortal, imperishable and eternal."
Which is OK. Brahman is Brahman, whether Nirguna or Saguna. Furthermore, since there is nothing other than Brahman in the world, all things are eternal including you and me. Form, birth and death are just 'maya', illusions. That is what Lord Krishna said in BhagawadGita:
"
na tu evāhaṁ jātu nāsaṁ, na tvaṁ neme janādhipāḥ;
na caiva na bhaviṣyāmaḥ, sarve vayam ataḥ param." BG 2.12
na - never; tu - but; eva - certainly; aham - I; jātu - at any time; na - did not; āsam - exist; na - not; tvam - you; na - not; ime - all these; jana-adhipāḥ - kings; na - never; ca - also; eva - certainly; na - not; bhaviṣyāmaḥ - shall exist; sarve vayam - all of us; ataḥ param - hereafter.
Never was there a time when I did not exist, nor you, nor all these kings; nor in the future shall any of us cease to be.