IIRC, the Pshat of the Torah clearly implies that the purpose of the Exodus was to inherit the Land of Israel, and G-d commands Bney Israel many times to enter the promised land, to settle it, etc. It is debatable whether this Mitzvah holds for generations but I don't think G-d would accept "no" as an answer (the whole generation was wiped for not agreeing to do so).
When the 2.5 tribes were impressed by the landscape and coveted it they came to Moses and asked to simply break the command (Num 32):
וַיָּבֹאוּ בְנֵי־גָד וּבְנֵי רְאוּבֵן וַיֹּאמְרוּ אֶל־מֹשֶׁה וְאֶל־אֶלְעָזָר הַכֹּהֵן וְאֶל־נְשִׂיאֵי הָעֵדָה לֵאמֹר ... אִם־מָצָאנוּ חֵן בְּעֵינֶיךָ יֻתַּן אֶת־הָאָרֶץ הַזֹּאת לַעֲבָדֶיךָ לַאֲחֻזָּה אַל־תַּעֲבִרֵנוּ אֶת־הַיַּרְדֵּן׃
the Gadites and the Reubenites came to Moses, Eleazar the priest, and the chieftains of the community, and said... "It would be a favor to us, if this land were given to your servants as a holding; do not move us across the Jordan.”
Moses behaves very weirdly in my opinion: he doesn't try to contact G-d for a piece of advice as he did with Bnot Zlofchad, he doesn't reprimand them for derailing from what seems to be the ultimate purpose of the Exodus, he's not puzzled after the lots were drawn and the land divided, instead, he says it's just fine as long as they don't convince others to join them and finish the conquest alongside the rest of the tribes.
IMHO, that looks like breaking the G-d's explicit command. Wasn't it? And why Moses played along instead of forcing them to follow the Heavenly plan?
