Early Roman and Indo-European timelines not precluded. You can also have those.
Then you have a TL where the "Southern Roman Empire", based in Carthage (it will likely conquer Rome at some point, but at that point, Rome is a mere regional town as it was in the 5th century and it's on the frontier so Carthage will stay the capital), is a major player. It's main enemies (or allies, depends) are whatever emerges out of the Germanic tribes in the north, the Eastern Roman Empire, the Arabs, and the Persians. The natural borders of this state are the Pyrenees (with the French Riviera), somewhere in northern Italy (maybe the Po River), the Balkan Coast, Eastern Anatolia, and the Zagros Mountains to the north/east, while to the south the borders are the Sahara Desert (probably instead called "Chenara" or something similar via a Berber loan instead of an Arab loan), the cataracts of the Nile, and the Syrian Desert. It would be a Romano-Berber state, much as the Frankish Empire fused Roman and Germanic influences, but I'd like to imagine that such a state could have more legitimacy via a Roman (like one of the Exarchs of Africa) ruler--the possibilities are endless via an earlier TL. My favourite TL for North Africa involves a Roman emperor conquering the rest of Mauretania (down to the Anti-Atlas Mountains at least, but ideally that too would later be conquered), leading to trade with the Canaries increased (basically leading to the Canaries becoming a "Hiberia" to the Mauretanian "Brittania"). At some point, the Canarian plant tagasaste comes to North Africa, making pastoralism (and agriculture in general) stronger and helping fight desertification/misuse of agricultural land. This could possibly extend pastoralism into lands unsuitable for it. Of course, it helps in Spain too. The Canarians themselves develop as good vassal states to Rome and end up pretty Romanised like other peoples on the periphery of Rome did.
With North Africa bigger and wealthier, it plays more of an influence in Roman politics (we'll assume things end up similar, like Rome still becomes Christian). The church in Carthage is perhaps more influential. Regardless, this all paves the way for a Southern Roman Empire. If the Vandals (say) conquer North Africa, then they could easily play the role the Franks did in Europe, right down to their homeland being named for them, like how "Gaul" is now "France", while "Africa [Proconsularis]" could be either "Vandalia", "Bandalia" (via known African Romance sound shifts) or "Andalia" (via a reborrowing of "Vandalia" from Berber). They'd be less numerous than the Franks were in Gaul, but you might have a high nobility of Vandals (who like OTL, assimilate quickly, with the main influence being mostly a few common personal names and maybe a toponym or loanword or two) and a lower nobility of Berbers and some remaining Roman elites.
Although no matter how the Southern Roman Empire evolves, it will likely have a lot of internal conflicts, especially with the Copts and Syriacs (who will likely benefit big time from them, if the Byzantines are their enemy--might as well phase out Greek and either do everything in Latin, or better yet, use the middle class/religious class and use Egyptian and Aramaic). In Europe local nobles could undermine them, as well as Papal politics (if the Pope is a puppet of the Southern Roman Empire or his Patriarch of Carthage, then imagine the power of the Antipope), and maybe you could have both a "Reconquista" from both Spain and Italy. A Romano-Berber Empire is huge for how medieval Europe evolves and how Christianity develops, so it could go in any direction.
As for the long term, I imagine that Romano-Berber North Africa (uniting either all of North Africa or just whoever rules coastal Mauretania from either Volubilis, Tingis, or Casablanca) could end up like Spain or Portugal and be keen sailors and colonialists. Brazil, South Africa, Australia, and the Southern Cone would be key targets for their colonialism, and perhaps create nations stronger than them (South Africa could evolve similarly to both Brazil and Argentina, albeit with less depopulation of natives). But they'd be similar to Spain in that Mauretania would likely be fighting in Spain, Africa/"Vandalia", etc. as well as dealing with sub-Saharan Africans, Native Americans, Asians, Australian Aboriginals. Of course, you could unite Africa and Mauretania and focus them toward colonialism (not a given--look how 16th-18th century France OTL focused on their European wars instead of long-term benefit in the Americas, Asia, etc.) instead of their no doubt numerous wars against Italian and Iberian powers and whoever else is in the Mediterranean, but at this point this just shows the many potential ways this scenario goes.