Seeking evidence-based methods to determine when “all-inclusive + airfare” bundles outperform DIY

I am trying to build a repeatable decision framework for budget travelers to evaluate whether an air-inclusive all-inclusive package (tour operator or OTA dynamic package) is financially superior to booking flights and lodging separately. Most discussions stop at headline price or food/alcohol consumption assumptions; I am interested in a comprehensive, normalized comparison that accounts for ancillary costs, risk transfer, and consumer protections.

Working assumptions and variables to normalize

Airfare type: bulk/IT/contract fares bundled with land can be materially cheaper but may have no mileage accrual, limited changes, and opaque fare rules. In contrast, retail fares may earn miles, include credit card protections, and allow self-rebooking.
Baggage and seat selection: package fares may include a checked bag on charters or certain tour operators; DIY with LCCs often adds bag and seat fees. Normalize by traveler’s actual baggage needs.
Ground transfers: many air-inclusive packages include roundtrip airport-hotel transfers; DIY often requires private shuttle/taxi costs. Include transfer time penalties if shared coaches add hours.
Resort scope: “all-inclusive” definitions vary (premium liquor, a la carte limits, motorized sports, adult-only zones, room service). Quantify expected out-of-pocket for exclusions and tipping policies.
Mandatory fees/taxes: resort fees, environmental levies, and departure taxes sometimes must be paid on-site and are not in the package headline. Include per-person and per-night components.
Occupancy effects: pricing is usually per person based on double occupancy; single supplements can erase savings. Children’s policies (kids-stay-free but pay airfare) change the calculus for families.
Seasonality and inventory: charter allotments and late-release “distressed inventory” can undercut DIY near departure, while peak school holidays often favor early DIY. Model time-to-departure as a variable.
Consumer protection: EU/UK package regulations (ATOL, Package Travel Directive) and some national schemes provide repatriation and linkage protection if flights change. Quantify the implicit “insurance value” versus DIY with separate suppliers.
Change/cancellation terms: compare deposit schedules, flexibility tiers, and reprice policies (e.g., free name changes on package charters vs airline change fees). Incorporate expected disruption probability by season/region.
Currency and payment: tour operators sometimes price in a fixed currency with hedged rates; DIY may expose you to FX swings and foreign transaction fees. Include cashback, voucher stacking, and card category bonuses.
Loyalty economics: loss of airline/hotel points on package rates versus DIY where points, status credits, and promos may offset cost. Assign a conservative cents-per-point valuation.
Trip duration and flight times: red-eyes that reduce a hotel night, forced overnights, and check-in/check-out alignment with flight schedules impact net nights enjoyed and food value.

Proposed comparison metric
For a given itinerary and party size, compute a per-person-per-night total cost inclusive of:

Base price paid to operator/suppliers
All taxes/fees paid locally
Expected ancillary spend for exclusions
Transportation to/from resort
Baggage and seat fees
Opportunity cost or gain from loyalty earnings/foregone earnings
Value of consumer protection and flexibility (can be proxied by market price of equivalent insurance or a risk-weighted expected loss)

Then, adjust for quality parity by scoring hotel category, room type, and on-site inclusions. If the package uses a charter with inferior flight times or connection risk, apply a utility penalty.

Targeted questions to the community
1) In which origin-destination pairs have you observed consistent price dominance of air-inclusive packages over DIY after full normalization? Examples sought: UK/EU to Canary Islands, Nordics to Med, US/Canada to Caribbean/Mexico, and long-haul beach (e.g., UK to Maldives/Mauritius).
2) For operators that use bulk/IT fares, which carriers and routes produce the largest airfare deltas versus public fares, and how often do these survive peak periods?
3) Which providers reliably include checked bags and private transfers in the air-inclusive price, materially shifting the comparison for budget travelers who would otherwise add those costs?
4) What are the best practices for leveraging late-release inventory without unacceptable risk (e.g., booking within 7-14 days), and how do rebooking policies compare if a storm or strike occurs?
5) Are there known cases where buying “land-only” invalidates transfers or onsite credits that would have been included with the air-inclusive bundle, reducing DIY’s apparent advantage?
6) For solo travelers and families of three or five, which configurations and destinations minimize single supplements or exploit kids-free policies when airfare is bundled?
7) Do packages booked through non-resident channels retain consumer protection (e.g., ATOL for non-UK residents), and how should that be valued in the model relative to standalone travel insurance?
8) Loyalty trade-offs: on which airlines do package/charter tickets still earn miles or status credit, and are there hotel chains that honor elite benefits on tour-operator rates enough to offset lost points?

Data request for benchmarking
If you have recent examples, please share anonymized data points:

Origin city, destination, dates, party composition
Operator/OTA, airline, hotel, board basis
Total price paid and itemized inclusions (bags, transfers)
Local fees paid on-site
Change/cancellation terms and applied promos/cashback
A DIY comparator with equivalent flights/room category and calculated ancillary costs

Edge-case insights that may move the needle

Caribbean/Mexico properties with high on-site taxes or mandatory sanitation fees not shown in cart
EU charter models (Jet2holidays, TUI, easyJet Holidays) where late-season packages bundle 22-23 kg baggage and undercut DIY by triple digits
US-origin dynamic packages that mask basic economy fare classes with no seat selection; the add-on for standard economy may erase savings
Destinations with airport departure taxes payable in cash where packages prepay on your behalf
Award-flight pairing with land-only AI: when does forfeiting included transfers negate the value of using miles?

The goal is to crowdsource a robust, destination- and season-specific playbook identifying when an air-inclusive all-inclusive is the rational budget choice after full-cost and risk normalization, and when DIY remains superior.