Where u/BobJoe39 addresses the development of France and England as cultural and political entities during the High and Late Medieval Period, this answer instead looks later in history toward the Early Modern Period (approximately 1492-1792). This is more in line with your comparison to the period of Habsburg primacy in Europe, as well as my area of comprehension.

France did not avoid participating in dynastic expansion. There is little differentiation between a “territorial” kingdom and a “dynastic” one, at least as I can recognize in the case of France. Europe was, as you state, ever changing due to royal marriages and inheritances. It was through that process that Habsburg dynasts came to rule Austria, Spain, and all their constituent subjects and territories. But France did not exclude itself from these kinds of dynastic feuds. It would be unfair to claim that the territories of France were not, to some extent, a “dynastic conglomeration of random territories” as the Habsburg Empire was. Rather, the expansion of both polities were often hodge-podge and lacking a cohesive nationalistic impetus. As you said, France would have only seemed relatively stable on a map; in its historical development, France was often at flux in regard to dynasties and royal families like every other European state.

French history leading up to the ascension of the House of Bourbon in 1589 saw France involved in many dynastic conflicts. For one, Anglo-French conflicts up to and ending with the Hundred Years’ War were typically related to it. Attempts by various English monarchs to unify their throne with that of France were ultimately repelled, but at times it appeared genuinely possible. The internal dynastic politics of England and France were complex, and oftentimes interweaving. In addition, the House of Valois, the royal house of France from 1328 to 1589, had cadet branches which ruled multiple disconnected territories. The House of Valois-Anjou were monarchs of Naples, and the House of Valois-Burgundy controlled Franche-Comté and most of the Low Countries. These territories would later be subsumed into other states: Aragon conquered the Kingdom of Naples in 1442, which in turn became subject to Spain during the merging of Aragon’s crown with Castille; and the territories of Burgundy were divvied between France and Austria following the War of the Burgundian Inheritance. And when Henry of Navarre of House Bourbon became King of France in 1589, he merged the kingdoms of Navarre and France.

Regions within France possessed significant rights and privileges leading into Early Modern Period. This meant the territories of France were quite disunited. As in most European countries, these regions had laws which granted economic privileges like tax exemptions and control over tariffs. Additionally, regions could express political influence through bodies like the Estates General. These rights would eventually be reduced, with great pushback, under King Louis XIV (reigned 1643-1715). France was also culturally diverse: France had many regional languages--including Frencien, Breton, Occitan, etc.--and religious affiliations--Southern France in the 12th century possessed a large Cathar population until the Albigensian Crusade (1209-1229), and a large Huguenot population in the 16th and 17th centuries until the Revocation of the Edict of Nantes (1685). These cultural diversities would make claims to a singular French culture or people difficult until the advent of modern theories of nationalism in the later 18th century.

In other words, France would at earlier points in its history be more accurately depicted as being a “bunch of random territories painted in the same color on maps,” as you described. That colouring scheme is not so much indicative of dynastic ownership, but of political influence. When various territories are loosely united under a composite state, such as Habsburg Spain and Austria, or pre-modern France, mapmakers might represent that by outlining internal divisions. However, as France become internally united through state policies in the 17th and 18th centuries, these divisions become less important to depict.

Additionally, Early Modern France developed as kingdom by dynastic means. France undertook actions similar to Habsburg expansion. For example, the Italian Wars (1494-1559) were instigated by French attempts to reclaim the throne of Naples. During the War of Devolution (1667-1668), Louis XIV claimed through dynastic right Spanish-held territories on France’s eastern border, including the Spanish Netherlands and the region of Franche-Comté. Most notably of all, France participated in the War of the Spanish Succession (1701-1714), where Louis XIV attempted to put a Bourbon king on the Spanish throne. A fierce multinational coalition opposed them, and although Louis succeeded in getting his grandson Philip (later King Philip V) on the Spanish throne, it was at the cost of renouncing any present or future union between France and Spain. To this day, the royal house of Spain is of the Bourbon dynasty. The territories over which France claimed dynastic ownership were sometimes gained and lost, just as territories between all nations were--France was not exceptional in this regard. If there were any factors responsible for France’s territorial consistency in this period, it had less to do with their motives for expansion and more to do with their military capacity and diplomatic ability to preserve their conquests.