Well obviously it would depend on exactly how the culture in question fought: the requirements of fighting mounted, or a culture that fought close rather than at a distance are different, so presumably different body types would be most suited.

Māori warfare of the 17th to 19th centuries is not by any stretch of the word 'ancient', but I suspect the mental parameters of your question were something like 'pre-gunpowder', so I'll talk a bit about how height and skill with weapons are related in traditional history. Plus I just want to write about it.

Traditional Māori battles were usually conducted at close quarters, with very limited armour or missile weapons. This is the kind of environment where one would expect height, and greater reach and stride length and weight, would be most likely to make a difference (though, due to the involvement of weapons, probably not as straightforwardly as, say, boxing), but the history is slightly more mixed. Many figures of traditional history are described as very tall, or essentially giants, and therefore as extremely dangerous in battle. Te-o-tane of the East Coast iwi of Ngāti Kahungunu, an eighth generation descendent of Kahungunu (whatever that is exactly, about the 17th century) is one (the following stories are taken from 'Takitimu'). When attacking a fortified place (pa) at Pakiaka, supposedly, as the defenders saw that as Te-O-Tane's party went through the deepest part of the river in front of the pa, the water reached up to his hips, but the arm-pits of his followers, decided to get out of there, and abandoned the pa. The tradition also dwells on the size and weight of his weapons: his patu (club) 'Te Ate-o-Hine-pehinga' and his taiaha long club 'Te Atero-o-Te-Arawhiti'. His heroic proportions are clearly treated as part of the reason he was so personally formidable, but he was also described as being technically skilled with his weapons as in his duel with Takapuwai (only having the english translation, and not knowing any mau rakau myself I wouldn't venture to interpret the text, but it says that Te-o-tane held his 'point downwards' and Takapuwai upwards.

Another couple of examples of how size was used in traditional history come from 'Ngāi Tahu: a migration history', the core of which is a group of tribal traditions collected in the 1930s by Arthur Carrington. Normally I'd be a little suspicious of details in a an english text with no translation, but it's edited by two academics who believe it's a pretty good handling of the traditional material. Anyway, during the early stages of the migration of Ngāi Tahu to the South Island (early estimates placed it at about 1677, more recent theories, taking into account generational overlap, have suggested as late as the mid 18th century), two prominent chiefs were Te Rākaitauheke, and his great nephew Maru. Their relative ages were rather more like uncle and nephew, Te Rākaitauheke was an undersized baby, and was going to be killed, before his older sister (Maru's grandmother) offered to raise him. He grew up to be a small man, and particularly wiry and hairy. Maru on the other hand was more typical of how ancestors of that time were pictured, being 'over seven feet tall and very heavily built' (he also had tendencies towards mercy to prisoners and offending his own relatives to reward his allies, neither of which were good things in his cultural context). Both Maru and Te Rākaitauheke are presented as great warriors, with Te Rākaitauheke being depicted charging ahead of his followers and routing enemies by himself. Te Rākaitauheke was also a great runner, and at the siege of Peketā, he was the initial decoy to entice the Ngāti Mamoe to pursue their party. After the pursuit had fairly started he wanted to keep fleeing until they reached some trees for easier cooking after the battle (even then the South Island was quite deforested), but Maru, saying 'it's the same bird in the morning as the evening' turned around, and with a patu in his right and left hand, struck down the first and second victims (the first kill or 'first fish' was considered to be very prestigious). He then had to ward off the Ngāti Mamoe spears on his own, until his brothers reached him.

To move on to more recent history, that likely represents real events in a much more straightforward way, there are several descriptions of chiefs in the early 19th century who had superior ability with weapons. This includes tall men like Te Wherowhero (later the first Māori King, Pōtatau), who in 1822 fought off several enemy chiefs during a retreat, while armed only with a kō or digging stick (though times had changed, this was only possible as Te Rauparaha restrained a man that was going to shoot him). It also includes Te Rauparaha (well known as the composer of the haka 'ka mate'), who was under five feet tall, but, though better known as a general, was also remembered to have been skilled with the taiha, defeating two enemy chiefs at once, and striking down four people with two blows.

TLDR From the legendary treatment of size, we can see that height was considered an advantage, and to be intimidating, but that the primary focus was on the notable deeds of well-born men of mana, and that their height was an aspect of their legend rather than its explanation, short men being shown performing equally impressive feats. To some extent this was borne out in real life: certain highly trained and naturally proficient warriors could completely outclass their enemies, and these individuals could be of any height, though better reach surely gave an advantage.

Sources for the early history bits Takitimu by J. H. Mitchell (Tiaki Hikawera Mitera) and 'Ngai Tahu a Migration History' mostly written by Hugh Carrington and edited by Te Maire Tau and Atholl Anderson.