If the Anatolian origin model is correct, the timeframe for the POD is too late.
If going with the Steppe model, which appears to attract more scholarly consensus, the best way to do it is to a have a stronger Tripol'ye culture, or, better yet, a Tripolye-derived culture that incorporates some of the advantages developed by the presumed speakers of Proto-Indeuropean (assumed to be the steppe cultures of the Dnieper, their eastern neighbors) and stays primarily agricultural while exapanding eastwards.
The presumed *IE speaking groups east of the Don (thought to be ancestral to Indo-Iranians and Tocharians in particular) would probably still be there and develop a pastoral economy with much of the same traits known historically, but they they may not spread westward in front of a mass of farmers all the way to the Don.
The collapse of Tripolye seems to be connected to climate change, but prior to that, about 4000 BCE, you may have an earlier assimilation of fully sedentary life by Western *IE speakers, which would in turn bring about at least partial linguistic assimilation.
You'd see much more continuity with Old Europe ITTL, and of course much more linguistic diversity in the subcontinent.
David Anthony suggested (but proof is thin) that Old European might be a branch of Afro-Asiatic, which would probably turn out to be the dominant language group in much of Europe ITTL. In the North, of course, Uralic would still probably dominate.