Small aircraft Flight Instructor expressed concern about terrain clearance issues within the airspace structure in the LAS area.

Narrative

Aircraft X training flight practicing cross-country VFR navigation east of Las Vegas airspace. Enroute to our return destination; HND; we received a yellow CAS for fuel. We stopped at ZZZ to visually confirm fuel; and fuel was above 'tabs.' We did a run-up and then continued west for a traditional arrival over VPVTR [visual point] into HND. Enroute; south of VPVDP; we received a red CAS for minimum fuel and so we began an immediate eastward arrival into Henderson through VPVDP. Although we visually confirmed fuel; I was unsure if the issue could be due to a sensor; onboard W&B (Weight and Balance) programming or very unlikely fuel starvation within the lines. We proceeded and requested our arrival with 'minimum fuel' as to be cautious. As we began to arrest our descent at 4500 ft. to avoid the overlying Class B and underlying terrain at VPVDP; I interpreted the engine performance to be less than expected at our present settings - 2660 RPM; approximately 26.5 in. Hg - and in anticipation of descending further; I proceeded further west to avoid the terrain. This; however; allowed only a small horizontal gap between the terrain and LAS Class B. Once clear of terrain; I immediately entered a 30-degree bank to avoid the Class B airspace; but I went into the controlled airspace by approximately 0.4 NM. HND ATC was on the phone with LAS TRACON at this time and the situation was resolved.To avoid future Class B conflicts; I will no longer look at the VPVDP arrival as an entry or exit point from HND airspace during training flights. The terrain clearance of 500 ft. and the airway horizontal / vertical restrictions from the Class B surface shelf are too limiting. Lastly; this same Class B shelf is only 1.4 NM from departure end of Runway 35L/R at HND; meaning most traditional GA aircraft with more than 200 HP must turn 'crosswind' below the FAA advised altitude of 700 ft. AGL; otherwise a Class B incursion is likely. I think it would be beneficial for the FAA to look at this sector of airspace once more to see if further adjustments are worth recommendation.